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diff --git a/macros/latex/contrib/cdpbundl/00readme.txt b/macros/latex/contrib/cdpbundl/00readme.txt
new file mode 100644
index 0000000000..56b06303e3
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/00readme.txt
@@ -0,0 +1,267 @@
+
+This is file `00readme.txt'.
+(Start your first tour of the C.D.P. Bundle by reading this file.)
+
+This file is part of a work named "C.D.P. Bundle".
+
+Copyright (C) 1999-2018 by Gustavo MEZZETTI
+                          <gustavo.mezzetti@istruzione.it>.
+
+The C.D.P. Bundle may be distributed and/or modified under the
+conditions of the LaTeX Project Public License, either version 1.3
+of this license or (at your option) any later version.
+The latest version of this license is in
+  http://www.latex-project.org/lppl.txt
+and version 1.3 or later is part of all distributions of LaTeX
+version 2005/12/01 or later.
+
+The C.D.P. Bundle has the LPPL maintenance status
+  "author-maintained".
+
+The file `manifest.txt' that comes along with this file specifies
+what the C.D.P. Bundle consists of; more precisely, it explains how
+the locutions "Work" and "Compiled Work", used in the LaTeX Project
+Public License, are to be interpreted in the case of this work.
+
+This file, after giving a brief description of the C.D.P. Bundle,
+explains how to install it and how to generate its--alas, still
+incomplete!--documentation.
+
+February 8, 2018 (vers. 0.36d)
+
+
+
+CONTENTS
+========
+
+- A dozen lines description of the software
+- Drawbacks
+- Installation in a snapshot
+- Checking the contents of the distribution
+- How to install the C.D.P. Bundle
+- How to generate the documentation
+- The makefile
+
+
+
+A DOZEN LINES DESCRIPTION OF THE SOFTWARE
+=========================================
+
+The C.D.P. Bundle was originally developed for a free association named
+"C.D.P." (more on it in the documentation), to typeset its official letters
+with the appropriate letterhead; but more generally, it can be used to
+typeset business letters bearing a letterhead of your choice and formatted
+according to Italian style conventions.  Its modular structure, however,
+provides you with building blocks of increasing level, by means of which
+you should be able to adapt the letter format to a wide variety of styles.
+It is also possible to write letters divided into sections and paragraphs,
+to include floating figures and tables, and to use the commands
+"\tableofcontents", "\listoffigures", and "\listoftables" to compile the
+relevant indexes.  A single input file can contain several letters, and
+each letter will have its own table of contents, etc., independent of the
+other ones.
+
+
+
+DRAWBACKS
+=========
+
+The documentation included in this distribution is absolutely minimal.  For 
+meaningful instructions on how to use the macros, the reader is referred to 
+other documents available at the web site of the past author's department, 
+which, however, are written in Italian.  Since the main purpose of these 
+macros is to typeset letters according to Italian conventions, this should 
+not be a problem.  I will consider translating the documentation in English 
+only if at least 5 persons ask me to.  Nobody has asked yet.
+
+
+
+INSTALLATION IN A SNAPSHOT
+==========================
+
+The C.D.P. Bundle is distributed in the usual .dtx + .ins format.  The main 
+file is `cdpbundl.dtx', with installation script `cdpbundl.ins'.  Do the 
+usual things to install it and to generate the documentation.  If you don't 
+know what the usual things are, read below.  Note that in order to generate 
+the documentation you should do the following:
+
+latex; latex; makeindex (.idx); makeindex (.glo); latex; latex.
+
+
+
+CHECKING THE CONTENTS OF THE DISTRIBUTION
+=========================================
+
+Before installing the C.D.P. Bundle and generating its documentation, it is 
+a good idea to read the file `manifest.txt', which lists all the files that 
+make up the distribution, to check that you don't lack any of them (in 
+particular, that you have the file `manifest.txt' itself!).  If you do find 
+that some files are missing, don't hesitate to complain to the distributor 
+from whom you obtained the others: this person, company, or institution is 
+infringing the copyright (actually, the copyleft) of the C.D.P. Bundle.  
+Please remember, however, that in order to comply with the copyright a 
+distributor is only requested to supply the files listed in `manifest.txt' 
+under the title "MEANING OF THE TERM `Work'", but not those listed under 
+"MEANING OF THE TERM `Compiled Work'".
+
+
+
+HOW TO INSTALL THE C.D.P. BUNDLE
+================================
+
+Note that in many pre-packaged TeX distributions, like MiKTeX and TeX Live, 
+the C.D.P. Bundle is already installed, and you can use it straight away.
+
+If, for some reason, you need to install the C.D.P. Bundle yourself, follow 
+these steps (but also see the section titled "The makefile", below):
+
+1) Make sure that the files `cdpbundl.dtx' and `cdpbundl.ins' are placed in 
+the same directory; below, we shall indicate this directory as "the current 
+directory".
+
+2) Run LaTeX (or plain TeX) once on the file `cdpbundl.ins'.  This will 
+generate, in the current directory, the following LaTeX input files:
+
+    articoletteracdp.cls
+    cdpaddon.sty
+    cdpbabel.sty
+    cdpnamesenglish.ldf
+    cdpnamesitalian.ldf
+    cdpshues-example.def
+    cdpshues.cfg
+    epson-stylus-740.def
+    hp-laserjet-4500.def
+    letteracdp.cls
+
+3) Move all the files listed in 2) from the current directory to a LaTeX 
+input directory--see b) and c) below.
+
+4) If you wish, delete the file `cdpbundl.log' to save disk space.
+
+Installation is now finished!  The following comments may be useful:
+
+a) The above listing of all the files you need to move is also displayed on 
+the terminal at the end of the run of the file `cdpbundl.ins'.
+
+b) The documentation of your TeX installation should tell you how to find 
+the LaTeX input directory/ies, and probably also how to create new LaTeX 
+input directories reserved to hold your private classes and packages.
+
+c) If you are not able to find the LaTeX input directories, or you are not 
+allowed to modify them and cannot create your personal LaTeX input 
+directories, do this: place all the files listed under 2) above in any 
+directory of your choice (a newly created, empty directory would be the 
+best choice, however); then put all the LaTeX source files that you want to 
+typeset using the C.D.P. Bundle in that same directory.  Of course, this 
+solution becomes impractical if the number of such source files exceeds a 
+dozen or so; but for a few files you can do this way, at least until you 
+decide to finally learn how to create your private LaTeX input directories!  
+:-)
+
+d) You may also choose to install the C.D.P. Bundle inside the main texmf 
+tree of your TeX installation (as opposed to installing it inside a 
+directory devoted to private classes and packages).  In this case, note 
+that the TDS-compliant location for the C.D.P. Bundle, that is, the 
+directory inside which you should put all the files listed in 2), is
+
+    tex/latex/cdpbundl/
+    
+The documentation, on the other hand, should be stored inside
+
+    doc/latex/cdpbundl/
+
+Of course, in order to do so you must have appropriate access priviledges 
+to the texmf tree of your site.
+
+
+
+HOW TO GENERATE THE DOCUMENTATION
+=================================
+
+A shortened form of the documentation, already typeset and packaged in PDF, 
+is provided in the file `cdpbundl-doc.pdf' that you might have found on 
+some sites (e.g., the CTAN sites).  This file, however, is not part of the 
+C.D.P. Bundle and distributors are not requested to include it among the 
+distributed files.  Moreover, it does not contain any implementation notes 
+(in which most users, though, are not at all interested).
+
+If the distributor from whom you obtained the C.D.P. Bundle did not provide 
+the file `cdpbundl-doc.pdf', or if you want the full documentation, 
+complete with all the available implementation notes (but, alas, still 
+unfinished for many respects), you can generate it following these steps 
+(but also see the section titled "The makefile", below):
+
+1) Run LaTeX (_not_ plain TeX) _twice_ on the file `cdpbundl.dtx'.
+This, among other things, will generate the files `cdpbundl.idx' and 
+`cdpbundl.glo' in the same directory as the file `cdpbundl.dtx'.
+
+2) Run MakeIndex on the file `cdpbundl.idx' obtained in 1), using the style 
+file `gind.ist', which is part of the standard LaTeX distribution.
+
+3) Run MakeIndex on the file `cdpbundl.glo' obtained in 1), using the style 
+file `gglo.ist', which is part of the standard LaTeX distribution, and 
+specifying the file `cdpbundl.gls' as the output file.
+
+4) Run LaTeX _two_ more times on the file `cdpbundl.dtx'.
+
+5) If you wish, you can now delete the following files, to save disk space:
+
+    cdpbundl.aux
+    cdpbundl.glo
+    cdpbundl.gls
+    cdpbundl.idx
+    cdpbundl.ilg
+    cdpbundl.ind
+    cdpbundl.lof
+    cdpbundl.log
+    cdpbundl.out
+    cdpbundl.toc
+
+After step 4), you should get the documentation in DVI format in the file 
+`cdpbundl.dvi', located in the same directory as `cdpbundl.dtx', with all 
+indexes, table of contents, etc. correctly set.
+
+However, if you are neurotic (as I am) and have a fast computer, you could 
+run LaTeX three or four times, instead of two, in step 1)...  :-)
+
+Other LaTeX typesetting engines should work in the same way, perhaps 
+producing the output in a different format; for example, you may use 
+pdflatex in place of LaTeX to obtain the documentation in PDF.
+
+
+
+THE MAKEFILE
+============
+
+Starting with version 0.36 of the C.D.P. Bundle, a (quite trivial!) 
+makefile that "knows" how to produce the documentation is offered along 
+with the Bundle itself.  Although it is not a required part of the 
+distribution (as per LPPL), you may find that some distributors supply it 
+all the same (I hope the CTAN sites will do so).  With this makefile in 
+the same directory as `cdpbundl.dtx', the shell command
+
+    make doc
+
+will take all the necessary actions to produce the full documentation
+(in PDF; the modifications you need to introduce into the makefile
+in order to obtain DVI output should be quite obvious, however).
+
+The same makefile can also be used to extract the various class, package, 
+and ancillary (definition and configuration) files: simply issue the 
+command
+
+    make code
+
+at the shell prompt; whereas
+
+    make
+
+will _both_ extract the code _and_ typeset the documentation.  Type
+
+    make help
+
+for more information.
+
+
+Have fun with the C.D.P. Bundle!
+
diff --git a/macros/latex/contrib/cdpbundl/Makefile b/macros/latex/contrib/cdpbundl/Makefile
new file mode 100644
index 0000000000..ac43bf4094
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/Makefile
@@ -0,0 +1,131 @@
+# makefile
+#
+# 2018 Feb 08
+#
+# Macro definitions
+ROOT_NAME	= cdpbundl
+DTX_NAME	= $(ROOT_NAME).dtx
+INS_NAME	= $(ROOT_NAME).ins
+DOC_AUX_FIL	= $(ROOT_NAME).aux $(ROOT_NAME).log \
+				$(ROOT_NAME).glo $(ROOT_NAME).gls \
+				$(ROOT_NAME).idx $(ROOT_NAME).ind \
+				$(ROOT_NAME).ilg $(ROOT_NAME).glg \
+				$(ROOT_NAME).toc $(ROOT_NAME).lof \
+				$(ROOT_NAME).hd  $(ROOT_NAME).out
+DOCUM_FILE	= $(ROOT_NAME).pdf
+CODE_FILES	= letteracdp.cls \
+				articoletteracdp.cls \
+				cdpaddon.sty \
+				cdpbabel.sty \
+				*.ldf \
+				*.def \
+				cdpshues.cfg
+#
+LATEX		= pdflatex
+MAKEINDEX	= makeindex
+
+#
+define GEN_FAKE_INDEX
+	@echo '\\begin{theindex}' > $(ROOT_NAME).ind
+	@echo '\\end{theindex}'  >> $(ROOT_NAME).ind
+	@echo "Generating fake .ind file."
+endef
+#
+define GEN_FAKE_GLOSSARY
+	@echo '\\begin{theglossary}' > $(ROOT_NAME).gls
+	@echo '\\end{theglossary}'  >> $(ROOT_NAME).gls
+	@echo "Generating fake .gls file."
+endef
+
+
+
+.PHONY: default
+.PHONY: code doc
+.PHONY: clean cleandoc cleanaux cleancode cleanall
+.PHONY: help
+
+# Default target
+default: doc code
+
+# Generating the code
+################################################################
+#                                                              #
+#   PLEASE NOTE THAT THE INSTALLER SCRIPT IS EXECUTED WITH     #
+#       openout_any=r                                          #
+#                                                              #
+################################################################
+code:
+	openout_any=r tex $(INS_NAME)
+
+# Generating the documentation
+doc: $(DOCUM_FILE)
+
+$(DOCUM_FILE): $(DTX_NAME)
+# Hack for getting index and glossary in the toc since first run:
+	$(GEN_FAKE_INDEX)
+	$(GEN_FAKE_GLOSSARY)
+# We know how many runs are needed:
+	$(LATEX) $(DTX_NAME)
+	$(LATEX) $(DTX_NAME)
+	$(MAKEINDEX) -s gind.ist -t $(ROOT_NAME).ilg -o $(ROOT_NAME).ind \
+			$(ROOT_NAME).idx
+	$(MAKEINDEX) -s gglo.ist -t $(ROOT_NAME).glg -o $(ROOT_NAME).gls \
+			$(ROOT_NAME).glo
+	$(LATEX) $(DTX_NAME)
+	$(LATEX) $(DTX_NAME)
+
+# Cleaning up: command "make clean" defaults to "make cleanall"
+clean: cleanall
+
+# Cleaning the code files
+cleancode:
+	-rm $(CODE_FILES)
+
+# Cleaning the documentation files
+cleandoc: cleanaux
+	-rm $(DOCUM_FILE)
+
+# Cleanng just the auxiliary files used in producing the documentation
+cleanaux:
+	-rm $(DOC_AUX_FIL)
+
+# Cleaning up all the generated files
+cleanall: cleancode cleandoc
+
+# Giving help
+help:
+	@echo "Here is a list of the available commands:"
+	@echo
+	@echo "  make"
+	@echo "    Generate both the code and the documentation (see below)."
+	@echo
+	@echo "  make code"
+	@echo "    Generate the LaTeX sources for all the classes, packages,"
+	@echo "    definition files, etc. of the C.D.P. Bundle; these files go"
+	@echo "    into the LaTeX input directories."
+	@echo
+	@echo "  make doc"
+	@echo "    Generate the documentation (in PDF); the resulting PDF file"
+	@echo "    goes into the LaTeX documentation directories (the auxiliary"
+	@echo "    files may be discarded)."
+	@echo
+	@echo "  make clean"
+	@echo "  make cleanall"
+	@echo "    These two commands are synonyms; they remove all of the"
+	@echo "    generated files (both code and documentation)."
+	@echo
+	@echo "  make cleancode"
+	@echo "    Remove the LaTeX source files (the \"code files\")."
+	@echo
+	@echo "  make cleandoc"
+	@echo "    Remove the documentation, together with all the auxiliary"
+	@echo "    files used to generate it."
+	@echo
+	@echo "  make cleanaux"
+	@echo "    Remove only the auxiliary files used to generate the"
+	@echo "    documentation."
+	@echo
+	@echo "  make help"
+	@echo "    Print this help message."
+	@echo
+
diff --git a/macros/latex/contrib/cdpbundl/README b/macros/latex/contrib/cdpbundl/README
new file mode 100644
index 0000000000..a66239f197
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/README
@@ -0,0 +1,34 @@
+(Version indicator: 2018 Feb 08)
+
+The C.D.P. Bundle was originally developed for a free association named
+"C.D.P." (more on it in the documentation), to typeset its official letters
+with the appropriate letterhead; but more generally, it can be used to
+typeset business letters bearing a letterhead of your choice and formatted
+according to Italian style conventions.  Its modular structure, however,
+provides you with building blocks of increasing level, by means of which
+you should be able to adapt the letter format to a wide variety of styles.
+It is also possible to write letters divided into sections and paragraphs,
+to include floating figures and tables, and to use the commands
+"\tableofcontents", "\listoffigures", and "\listoftables" to compile the
+relevant indexes.  A single input file can contain several letters, and
+each letter will have its own table of contents, etc., independent of the
+other ones.
+
+The C.D.P. Bundle may be distributed and/or modified under the
+conditions of the LaTeX Project Public License, either version 1.3
+of this license or (at your option) any later version.
+
+For more information, read the following files:
+
+00readme.txt        --  start by reading this file
+cdpbundl-doc.pdf    --  overview of the C.D.P. Bundle (PDF)
+cdp-ver-0-36.pdf    --  instructions specific to version 0.36 (PDF)
+
+Other files that make up the distribution are:
+
+manifest.txt    --  legal stuff
+cdpbundl.dtx    --  main source file
+cdpbundl.ins    --  installation script
+
+See the file `manifest.txt' for a more precise specification of what
+files constitutes a LPPL-compliant distribution.
diff --git a/macros/latex/contrib/cdpbundl/cdp-ver-0-36.pdf b/macros/latex/contrib/cdpbundl/cdp-ver-0-36.pdf
new file mode 100644
index 0000000000..853cac7aa8
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/cdp-ver-0-36.pdf
diff --git a/macros/latex/contrib/cdpbundl/cdp-ver-0-36.tex b/macros/latex/contrib/cdpbundl/cdp-ver-0-36.tex
new file mode 100644
index 0000000000..87e3cc0b7f
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/cdp-ver-0-36.tex
@@ -0,0 +1,1107 @@
+\begin{filecontents}{myarticletter.cls}
+\NeedsTeXFormat{LaTeX2e}[1998/06/01] % LaTeX2e is required!
+\ProvidesClass{myarticletter}
+              [2018/02/08 v0.03 (development)]
+\LoadClassWithOptions{articoletteracdp}[2018/02/08]
+\input{mylogo.def}
+\endinput
+\end{filecontents}
+
+
+
+\begin{filecontents}{mylogo.def}
+\ProvidesFile{mylogo.def}[2018/02/08 v0.03 (development)]
+
+\RequirePackage[customletterhead]{cdpaddon}[2018/02/08]
+\RequirePackage{color}
+
+\DeclareFontFamily{T1}{my@calli}{}
+\DeclareFontShape{T1}{my@calli}{m}{n}{<->s*[1.44]callig15}{}
+\definecolor{my@lh@color}{rgb}{0,.4,.4}
+
+\begin{customletterhead}{\textwidth}
+    \color{my@lh@color}
+    \fontsize{17}{21}\usefont{T1}{my@calli}{m}{n}
+    \leftline{%
+        \setlength{\unitlength}{1cm}%
+        \begin{picture}(0,0)
+            \put(-2,0){\framebox(1.8,1.2){%
+                \normalsize\ttfamily My Logo%
+            }}
+        \end{picture}%
+        My Company'\,s Letterhead\enspace
+        \hrulefill\hspace{-2cm}%
+    }
+\end{customletterhead}
+
+\settowidth{\longindentation}{%
+    \fontsize{17}{21}\usefont{T1}{my@calli}{m}{n}%
+    My Company'\,s Letterhead\enspace
+}
+
+\begin{customletterfoot}{\textwidth}
+    \color{my@lh@color}
+    \fontsize{5}{6}\usefont{T1}{pplx}{m}{n}
+    \raggedleft
+    \ruleacrossheadorfoot[-2cm]
+    My (almost unreadable) \textsc{small print},\\
+    aligned along the \textit{right} edge\\
+    of the main text.
+\end{customletterfoot}
+
+\renewcommand*{\foldingtagrule}{%
+    \color{my@lh@color}\CDPFactoryFoldingTagRule
+}
+
+\endinput
+\end{filecontents}
+
+
+
+\documentclass
+    [twoside,boldsubject,italicsignature,shortindent,signaturerule]
+    {myarticletter}[2018/02/08]
+\usepackage[T1]{fontenc}
+\usepackage[english]{cdpbabel}
+\usepackage[bookmarksnumbered,hypertexnames=false]{hyperref}
+\usepackage{lipsum}
+
+\name{Gustavo Mezzetti}
+\signature{Gustavo Mezzetti}
+\address{
+    Gustavo \textsc{Mezzetti}\\
+        \protect\href
+            {mailto:gustavo.mezzetti@istruzione.it}
+            {\nolinkurl{gustavo.mezzetti@istruzione.it}}
+}
+\date{February~8, 2018}
+
+\hypersetup{
+    pdftitle        = {The C.D.P. Bundle version 0.36},
+    pdfauthor       = {G. Mezzetti},
+    pdfsubject      = {Instructions on how use the C.D.P. Bundle},
+    pdfcreationdate = {D:20180208120000},
+    pdfmoddate      = {D:20180208120000}
+}
+
+\pagestyle{headings}
+\setcounter{tocdepth}{2}
+
+\newcommand*{\pdfbslash}{}
+{\catcode`\|=0 |catcode`|\=12 |gdef|pdfbslash{\\}}
+
+\DeclareRobustCommand*{\packlass}[1]{{\normalfont\sffamily #1}}
+\DeclareRobustCommand*{\opz}[1]{{\normalfont\ttfamily #1}}
+\DeclareRobustCommand*{\env}[1]{%
+    {\texorpdfstring{\normalfont\ttfamily}{}#1}%
+}
+\DeclareRobustCommand*{\sty}[1]{{\normalfont\ttfamily #1}}
+\DeclareRobustCommand*{\filedir}[1]{{\normalfont\ttfamily #1}}
+\DeclareRobustCommand*{\cntr}[1]{{\normalfont\ttfamily #1}}
+\DeclareRobustCommand*{\command}[1]{%
+    {\texorpdfstring{\normalfont\ttfamily \char\escapechar}{\pdfbslash}#1}%
+}
+\newcommand*{\meta}[1]{\(\langle\textit{#1}\rangle\)}
+\newcommand*{\strongemph}[1]{\textbf{#1}}
+\newcommand*{\zerolistvertspaces}{%
+    \setlength{\parskip}{0pt}%
+    \setlength{\topsep}{\parskip}%
+    \setlength{\partopsep}{\parskip}%
+}
+
+\newcommand*{\lcdp}{\packlass{letteracdp}}
+\newcommand*{\acdp}{\packlass{articoletteracdp}}
+\newcommand*{\hyre}{\packlass{hyperref}}
+\newcommand*{\cdpa}{\packlass{cdpaddon}}
+\newcommand*{\adic}{\packlass{lettcdpadi}}
+\newcommand*{\adip}{\packlass{adiseal}}
+\newcommand*{\babel}{\packlass{babel}}
+\newcommand*{\cdpbabel}{\packlass{cdpbabel}}
+\newcommand*{\Bundle}{C.D.P. Bundle}
+\newcommand*{\oclh}{\opz{customletterhead}}
+\newcommand*{\eclh}{\env{customletterhead}}
+\newcommand*{\eclf}{\env{customletterfoot}}
+
+\makeatletter
+
+\newcounter{listing}[letter]
+\renewcommand*\thelisting{\@arabic\c@listing}
+\@ifdefinable\fps@listing{\def\fps@listing{tbp}}
+\@ifdefinable\ftype@listing{\def\ftype@listing{4}}
+\@ifdefinable\ext@listing{\def\ext@listing{lol}}
+\@ifdefinable\fnum@listing{\def\fnum@listing{\listingname~\thelisting}}
+\newenvironment*{listing}
+               {\@float{listing}}
+               {\end@float}
+\newenvironment*{listing*}
+               {\@dblfloat{listing}}
+               {\end@dblfloat}
+\newcommand*\listoflistings{%
+  \section*{\listlistingname \sectionmark\listlistingname}%
+  \if@loX@in@toc@
+    \addcontentsline{toc}{section}{\protect\listlistingname}%
+  \fi
+  \@starttoc{lol}%
+}
+\@ifdefinable\l@listing{\let\l@listing\l@figure}
+\newcommand*\listlistingname{List of listings}
+\newcommand*\listingname{Listing}
+\@ifdefinable\toclevel@listing{\def\toclevel@listing{\toclevel@figure}}
+% Note that we use "\def" here, not "\let".
+
+\newcommand*\cleantop{%
+    \dimen@ \baselineskip
+    \advance \dimen@ -\topskip
+    \prevdepth \dimen@
+}
+\newcommand*\cleanbot{%
+    \dimen@ \baselineskip
+    \advance \dimen@ -\topskip
+    \advance \dimen@ -\prevdepth
+    \vskip \dimen@
+    \prevdepth \z@
+}
+\newcommand*\cleanbotp{%
+    \vskip -\prevdepth
+    \prevdepth \z@
+}
+
+\makeatother
+
+\hfuzz = 0pt
+\vfuzz = 0pt
+
+
+
+
+
+
+\begin{document}
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%                              %
+%       Letter no. 1           %
+%                              %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\begin{letterhead}[Whom it may concern]{
+    To whom may be concerned\\
+    with writing letters with \LaTeX\\
+    (and want them to bear a letterhead
+    of \emph{their own} choice!)
+}[
+    The \Bundle\ version 0.36.
+]
+
+\opening{Dear friends:}
+
+This letter describes the new ``bells and whistles'' that have been made
+available in version~0.36 of the \Bundle.  This version is just a provisional
+patch applied on what essentially remains ``fossil'' code, in need of a thorough
+redesign; nonetheless, it does provide some long-awaited features, most
+prominently the ability to modify, with reasonable ease, the letterhead produced
+by the \env{letterhead} environment.
+
+The author wishes to thank Lorenzo Pantieri for having promoted, in his
+excellent work
+``\href{http://www.lorenzopantieri.net/LaTeX_files/Complementi.pdf}
+{\emph{Complementi all'Arte di scrivere con \LaTeX}}'' (``Additions to The art
+of writing with \LaTeX''), the use of the \lcdp\ document class, which is the
+main component of the \Bundle.  This letter (indirectly) uses the \acdp\
+document class.
+
+
+
+\tableofcontents
+\listoflistings
+
+
+
+\setcounter{secnumdepth}{0}
+
+\section{Introduction}
+
+The \Bundle\ was essentially written between 1999 and 2000 (for an Italian
+audience), and even at that time it contained code that was already deprecated;
+even worse, its design was flawed since the beginning, because it had been
+conceived for a specific and limited application (the letters of the C.D.P.,
+exactly), and was adapted for more general use only as an afterthought.
+
+A thorough redesign would therefore be needed; on the other hand, some users
+have suggested, or asked for, improvements and additions, in particular for what
+concerns the use of the bundle with other languages besides Italian (see
+Section~\ref{S:Languages}), that can be implemented rather easily by means of
+provisional patches.  I~have already been deferring the introduction of these
+comparatively harmless enhancements for five years, waiting for the right moment
+to undertake the task of redesigning the bundle from scratch, but now I~have
+resolved to simply patch up the existing version.
+
+The version herein presented, therefore, is far from being optimal: no serious
+attempt has been made to remove ``fossil'' code, nor to bring it up to date with
+modern \LaTeX\ usage.  I~have removed, however, the \adip\ package and the
+\adic\ document class, of which, probably, nobody besides me even remembers the
+purpose.
+
+Though\marginpar{\hfill\strongemph{$*{*}*\;$WOW!!$\;*{*}*$}},
+% Yes, I know, I should use \textasteriskcentered...
+\strongemph{good news} are coming for all those users who asked for a means to
+\strongemph{customize the letterhead} produced by the \Bundle: a reasonably
+viable method for doing so has been provided at
+last!~\facesmile\facesmile\facesmile\space The method requires the use of the
+\cdpa\ package, passing in the new option \oclh.  You can specify the contents
+of your custom head and foot by means of two new environments, called \eclh\ and
+\eclf, which are similar, to a certain extent, to the \env{minipage}
+environment.  This should give you the maximum freedom in designing the
+letterhead (having recourse to \env{picture}s and images, if you wish to),
+whilst adopting an interface you are surely well familiar with.  See
+Section~\ref{S:Letterhead} for more information.
+
+Another nifty feature is the ability to draw a thin rule to guide your hand in
+signing your letters: you ask for this behavior by passing the new
+\opz{signaturerule} option to the \lcdp\ document class.  See
+Section~\ref{S:Options} for more information.
+
+Finally, some minor corrections of an aesthetic nature have also been brought
+in, which are concisely discussed in Section~\ref{S:Adjustments}.
+
+
+
+\setcounter{secnumdepth}{2}
+
+\section{My own letterhead, at last!}
+\label{S:Letterhead}
+
+One of the questions that users ask most frequenty about the \Bundle\ is perhaps
+``How the hell can I~put \emph{my own} letterhead in the place of that silly
+greenish thing?''; so, let's start with this one!
+
+%%%%
+\begin{listing}[p]
+    \cleantop
+\begin{verbatim}
+\documentclass
+    [twoside,boldsubject,italicsignature,shortindent,signaturerule]
+    {letteracdp}[2018/02/08]
+\usepackage[T1]{fontenc}
+\usepackage[english]{cdpbabel}
+\usepackage[customletterhead]{cdpaddon}[2018/02/08]
+\usepackage{url,lipsum}
+
+\address{
+    Gustavo \textsc{Mezzetti}\\
+    \protect\url{gustavo.mezzetti@istruzione.it}
+}
+\signature{Gustavo Mezzetti}
+\date{February~8, 2018}
+\place{Padova}
+
+
+
+% Definition of your letterhead occurs here:
+
+\begin{customletterhead}{\textwidth}
+    \centering \Huge
+    My Huge Centered Letterhead
+\end{customletterhead}
+\begin{customletterfoot}{\textwidth}
+    \raggedleft \tiny
+    \ruleacrossheadorfoot
+    My (almost unreadable) small print\\
+    flushed against the right margin.
+\end{customletterfoot}
+
+
+
+\begin{document}
+
+\begin{foldedletterhead}[Whom it may concern]
+    {To whom it may concern}
+    [My own letterhead, at last!]
+
+\makepresentation
+\maketopdate\relax
+
+\lipsum[1-2]
+
+\makesignature
+
+\end{foldedletterhead}
+
+\end{document}
+\end{verbatim}
+    \caption{How to customize the letterhead}
+    \label{lis:customletter}
+    \cleanbotp
+\end{listing}
+%%%%
+
+
+
+\paragraph{For the impatient}
+\label{P:LetterHeadImpatient}
+
+Listing~\ref{lis:customletter} explains what you have to do, in order to define
+a simple customized letterhead, by means of a practical example.  It shows the
+complete contents of the \LaTeX\ source file: by mimicking this code, you should
+easily obtain what suits your needs.  Let us skim briefly through it.
+
+First of all, note that we load the \cdpa\ package, with the \oclh\ option (as
+well as a few other useful packages that, of course, have nothing to do with
+letterheads).  Then come the usual declarations concerning the sender, the date,
+etc.
+
+Still in the preamble---as we will soon see, we could do this in other places
+too, but also the preamble is absolutley OK\@---we start a \eclh\ environment.
+This environment has the following synopsis:
+%
+\begin{flushleft}
+    \verb|\begin{customletterhead}{|\meta{wdth}\verb|}|\quad
+    \meta{text}\quad
+    \verb|\end{customletterhead}|
+\end{flushleft}
+%
+As you can see, it resembles a \env{minipage} environment, except that you
+cannot specify the vertical alignment of the material contained therein (because
+you don't need to: the mini page you are producing has not to be aligned with
+any nearby constructs); and indeed, it creates a ``mini page'' of width
+\meta{wdth} containing the \meta{text} you specify.  This \meta{text} should be
+your letterhead: for example, the code shown here will produce a letterhead,
+centered between the margins of the body of the main text, which reads ``My Huge
+Centered Letterhead''---and actually looks like that!~\facesmile
+
+Next, we do the same for the footer, using the \eclf\ environment, which is
+syntactically identical to \eclh:
+%
+\begin{flushleft}
+    \verb|\begin{customletterfoot}{|\meta{wdth}\verb|}|\quad
+    \meta{text}\quad
+    \verb|\end{customletterfoot}|
+\end{flushleft}
+%
+By examining the code, you can easily tell that, this time, the footer will be
+aligned against the right margin (\verb|\raggedleft|) and set in \verb|\tiny|
+type---which is what the text itself says, after all.  But what does the
+\verb|\ruleacrossheadorfoot| command do?  Well, it simply draws a horizontal
+rule, which\ldots\ yes, extends across the whole footer.  You could use one of
+the standard commands for producing rules, here (\LaTeX's \verb|\rule|, plain
+\TeX's \verb|\hrule|), but this one has been specifically crafted for use inside
+the two abovementioned environments; it consumes no vertical space, and does not
+alter the distance (\verb|\baselinekip|) between the baselines of adjacent lines
+of text.  Moreover, it can take optional arguments to modify its appearance, as
+we shall see \hyperref[P:FinePoints]{in a minute}.
+
+You can try out this example by yourself (I~advise you to do so), but for your
+convenience the output it typesets is reproduced in a separate letter that you
+find enclosed with this one, just after it in this same file.  If you have a
+look at the result, you will be glad to note that the thin sign that the
+\env{foldedletterhead} environment is supposed to draw along the right edge of
+the sheet, to mark the exact point where it should be folded, is drawn also when
+the original letterhead is replaced by yours.  This is just fine (but see also
+Paragraph~\ref{P:FinePoints}).
+
+
+
+\paragraph{A deeper look}
+\label{P:Deeper}
+
+As you, certainly, have already guessed, the two environments introduced
+\hyperref[P:LetterHeadImpatient]{above} simply save their contents into a box;
+the \oclh\ option causes these two boxes to be used in place of the header and
+the footer, respectively, that had been originally defined by the \lcdp\
+document class.  More precisely, when the \oclh\ option is in force, a copy of
+those boxes is centered, with first-order infinite glue, in the header (resp.,
+in the footer) line, pretending that they have zero height and depth, with the
+bottom (resp., top) margin of the box defined by \eclh\ (resp., \eclf) aligned
+along the baseline of the header (resp., of the footer) line of the page.  Note
+that the \cdpa\ package defines the \eclh\ and \eclf\ environments, and their
+associated storage boxes, even if you do \emph{not} specify the \oclh\ option:
+this option simply dictates whether or not those two boxes should be \emph{used}
+for the letterhead.  This is good, since it means that the presence or absence
+of the \oclh\ option will not affect the \emph{syntax} of your document, but
+only the appearance of the typeset output, which is how options should behave.
+
+
+
+\paragraph{The letterhead is defined locally}
+\label{P:Local}
+
+As we indicated in Paragraph~\ref{P:LetterHeadImpatient}, the output produced by
+listing~\ref{lis:customletter} is shown in a separate letter enclosed after this
+one; you may be wondering how I~managed to produce two (or, actually, several)
+letters with different letterheads in a single \LaTeX\ run (yes, it \emph{was} a
+single run).  Well, I~am the author of the package, and I~could have played some
+nasty trick; but actually I~didn't need to, because the \eclh\ and \eclf\
+environments save their contents in their associated storage boxes
+\emph{locally}.  This means that if they are postioned \emph{within} the
+environment that produces a certain letter (say, \emph{e.g.},
+\env{foldedletterhead}), the header and the footer will be changed \emph{only}
+for that letter; for subsequent ones, the former header and footer will be
+reinstated.  Of course, the redefinitions must occur before the \verb|\opening|
+command (or anything else that typesets text).
+
+%%%%
+\begin{listing}[tbp]
+    \cleantop
+\begin{verbatim}
+\begin{foldedletterhead}[Someone Else]{
+    To Someone Else\\
+    Some other place\\
+    Some other city
+}[
+    Another letterhead.
+]
+
+\begin{customletterhead}{\textwidth}
+    \raggedright \Huge
+    A different head
+\end{customletterhead}
+\begin{customletterfoot}{\textwidth}
+    \centering
+    \ruleacrossheadorfoot
+    A different foot
+\end{customletterfoot}
+
+\opening{Dear Someone,}
+
+\lipsum[1-2]
+
+\closing{Best regards.}
+
+\end{foldedletterhead}
+\end{verbatim}
+    \caption{How to customize the letterhead for a single letter}
+    \label{lis:customletterlocal}
+    \cleanbot
+\end{listing}
+%%%%
+
+This point is further illustrated in listing~\ref{lis:customletterlocal}, which
+shows how to customize the letterhead for just a single letter.  This code has
+been copied and then pasted toward the end of this file, to show, in a third,
+independent letter, the output it produces.  Actually, for this I~\emph{did}
+have to play some tricks not included in the code of the listing, in order to
+``decolor'' the thin sign that marks the point where the sheet is to be folded,
+and to reset the value of the \verb|\longindentation| parameter; but both these
+changes can be made ``locally'' too.  There is a slight complication deriving
+from the fact that, in order for a change to \verb|\longindentation| to turn
+effective in a given ``letter-making'' environment, the change must occur
+\emph{outside} the ``letter-making'' environment itself: this forced me to
+supply an additional level of grouping.
+
+
+
+\paragraph{Your own classes for your own letterhead}
+\label{P:Classes}
+
+If you know \LaTeX\ well, there will probably be one last point that still
+bothers you.  We said, in Paragraph~\ref{P:LetterHeadImpatient}, that the \eclh\
+and \eclf\ environments can very well be embedded in the preamble, without
+causing any trouble: how come the typesetting that occurs inside these
+environments does not trigger the ``Missing \verb|\begin{document}|'' error?
+The answer is simply that these two environments have been specifically made
+exempt from this error, precisely in order to permit you to include them in the
+preamble too; and this, in turn, has been done because the concept of
+``preamble'' also covers the code included in custom classes that you write
+yourself.
+
+This means that you can write your own custom classes that produce your own
+custom letterhead, which is nice.~\facesmile\space We use the plural, because
+you will surely want to define customized versions of \emph{both} the \lcdp\
+class \emph{and} the \acdp\ class; the best way to do so is to write three
+distinct files, as we are now going to explain.
+
+%%%%
+\begin{listing}[p]
+    \cleantop
+\begin{verbatim}
+\NeedsTeXFormat{LaTeX2e} % LaTeX2e is required!
+\ProvidesClass{myletter}
+              [2018/02/08 v0.03 (development)]
+\LoadClassWithOptions{letteracdp}[2018/02/08]
+\input{mylogo.def}
+\endinput
+\end{verbatim}
+    \caption{Contents of the\/ \filedir{myletter.cls} file}
+    \label{lis:myletter}
+\end{listing}
+%%%%
+
+%%%%
+\begin{listing}[p]
+\begin{verbatim}
+\NeedsTeXFormat{LaTeX2e} % LaTeX2e is required!
+\ProvidesClass{myarticletter}
+              [2018/02/08 v0.03 (development)]
+\LoadClassWithOptions{articoletteracdp}[2018/02/08]
+\input{mylogo.def}
+\endinput
+\end{verbatim}
+    \caption{Contents of the\/ \filedir{myarticletter.cls} file}
+    \label{lis:myarticletter}
+\end{listing}
+%%%%
+
+%%%%
+\begin{listing}[p]
+    \cleantop
+\begin{verbatim}
+\ProvidesFile{mylogo.def}[2018/02/08 v0.03 (development)]
+
+\RequirePackage[customletterhead]{cdpaddon}[2018/02/08]
+
+\begin{customletterhead}{\textwidth}
+    \centering \Huge
+    My Huge Centered Letterhead
+\end{customletterhead}
+\begin{customletterfoot}{\textwidth}
+    \raggedleft \tiny
+    \ruleacrossheadorfoot
+    My (almost unreadable) small print\\
+    flushed against the right margin.
+\end{customletterfoot}
+
+\endinput
+\end{verbatim}
+    \caption{Contents of the\/ \filedir{mylogo.def} file}
+    \label{lis:mylogo}
+    \cleanbotp
+\end{listing}
+%%%%
+
+So, let us suppose that you want to define two custom classes, named
+\packlass{myletter} and \packlass{myarticletter}, respectively, that both
+produce the same letterhead as the one we saw in listing~\ref{lis:customletter}.
+For this, you write three files called \filedir{myletter.cls},
+\filedir{myarticletter.cls}, and \filedir{mylogo.def}, whose contents are
+reproduced in listings \ref{lis:myletter}, \ref{lis:myarticletter},
+and~\ref{lis:mylogo}, respectively.  As you can see, the purpose of
+\filedir{myletter.cls}\slash\filedir{myarticletter.cls} is just to supply ``glue
+code'' toward (the \lcdp\slash\acdp\ classes and) the \filedir{mylogo.def} file,
+which is the single place where the redefinition of the letterhead occurs.
+
+%%%%
+\begin{listing}[tbp]
+    \cleantop
+\begin{verbatim}
+\ProvidesFile{mylogo.def}[2018/02/08 v0.03 (development)]
+
+\RequirePackage[customletterhead]{cdpaddon}[2018/02/08]
+\RequirePackage{color}
+
+\DeclareFontFamily{T1}{my@calli}{}
+\DeclareFontShape{T1}{my@calli}{m}{n}{<->s*[1.44]callig15}{}
+
+\definecolor{my@lh@color}{rgb}{0,.4,.4}
+
+\begin{customletterhead}{\textwidth}
+    \color{my@lh@color}
+    \fontsize{17}{21}\usefont{T1}{my@calli}{m}{n}
+    \leftline{%
+        \setlength{\unitlength}{1cm}%
+        \begin{picture}(0,0) % you can use \includegraphics instead
+            \put(-2,0){\framebox(1.8,1.2){%
+                \normalsize\ttfamily My Logo%
+            }}
+        \end{picture}%
+        My Company'\,s Letterhead\enspace
+        \hrulefill\hspace{-2cm}%
+    }
+\end{customletterhead}
+
+\settowidth{\longindentation}{%
+    \fontsize{17}{21}\usefont{T1}{my@calli}{m}{n}%
+    My Company'\,s Letterhead\enspace
+}
+
+\begin{customletterfoot}{\textwidth}
+    \color{my@lh@color}
+    \fontsize{5}{6}\usefont{T1}{pplx}{m}{n}
+    \raggedleft
+    \ruleacrossheadorfoot[-2cm]
+    My (almost unreadable) \textsc{small print},\\
+    aligned along the \textit{right} edge\\
+    of the main text.
+\end{customletterfoot}
+
+\renewcommand*{\foldingtagrule}{%
+    \color{my@lh@color}\CDPFactoryFoldingTagRule
+}
+
+\endinput
+\end{verbatim}
+    \caption{Contents of a more elaborated\/ \filedir{mylogo.def} file}
+    \label{lis:mylogo-more}
+    \cleanbotp
+\end{listing}
+%%%%
+
+Listing~\ref{lis:mylogo-more} shows a more elaborate example of a
+\filedir{mylogo.def} file to go together with the same two class files shown in
+listings~\ref{lis:myletter} and~\ref{lis:myarticletter}.  Here we have added a
+touch of superior style not only by employing color and some fancy fonts, but
+also by having recourse to the fine adjustments described in
+\hyperref[P:FinePoints]{the next paragraph} (because of the fonts, this example
+might not work on all \TeX\ installations).  The letterhead defined by this
+example is exactly the same as the one this letter itself bears on its first
+page.
+
+
+
+\paragraph{Fine points of style}
+\label{P:FinePoints}
+
+The first fine point of style that should be noted in
+listing~\ref{lis:mylogo-more} is that the \verb|\longindentation| rigid length
+is set equal to the width of the writing of the letterhead (``My Company's
+Letterhead'').  Since the ``letter-making'' environments indent the address of
+the addressee precisely by the amount of \verb|\longindentation|, this will
+cause such addresses to be neatly aligned with a visually relevant element of
+the design of the letterhead (the rule on the right); you should do the same
+with your own letterhead, if it contains a similarly relevant component.  If you
+do not yourself assign it a value, \verb|\longindentation| is set to half the
+value of \verb|\textwidth|.
+
+The second fine point to note is that the sign that marks the fold is drawn in
+the same color as the rest of the letterhead.  The \Bundle\ computes the
+vertical position of this sign, but to actually draw it, it calls the
+\verb|\foldingtagrule| command, which the end user can redefine.  This command
+works similarly to \verb|\footnoterule|, and, like the latter, should take up no
+vertical space.  Its ``factory'' definition is backed up in the
+\verb|\CDPFactoryFoldingTagRule| command (which should \emph{never} be
+redefined, of course); as you can see, in listing~\ref{lis:mylogo-more} we
+redefine \verb|\foldingtagrule| to simply invoke the factory default after
+setting the appropriate color.
+
+The third, and last, point to note is that the \verb|\ruleacrossheadorfoot|
+command can get an optional argument in which an inset from the text margins can
+be specified; a \emph{negative} inset, like here, causes the rule to protrude
+into the margins.  A second optional argument let you indicate different insets
+for the left and the right margin, in this order.  Note that these arguments
+\emph{must} contain \emph{rigid} lengths.
+
+
+
+\section{Other languages besides Italian}
+\label{S:Languages}
+
+Like many other document classes and packages, the classes of the \Bundle\ mark
+up some portions of the output they produce by adding certain descriptive
+strings, that, by default, are written in Italian.  For example, when you have
+requested the \sty{headings} page style, the name of the addressee, which is
+printed atop pages, is preceded by the string ``\emph{A:}'' (=~``To:'');
+similarly, when you issue the command \verb|\tableofcontents| in a documents
+that adopts the \acdp\ document class, the table it produces is titled
+``\emph{Sommario}'' (=~``Contents''); and so on.
+
+When the \Bundle\ was used only by the members of the \emph{Coordinamento}, the
+Italian defaults it provided for those captions were, of course, quite adequate;
+as long as its use remained confined to the Italian \LaTeX\ community, they were
+still acceptable; but now, questions about how to adapt the \Bundle\ to foreign
+languages have begun to be asked in some Internet forums by users around the
+world, pushing me to reconsider the matter.
+
+Of course, the Italian captions are not (nor they have ever been) ``hard-wired''
+in the code: they are defined by macros that follow the usual naming conventions
+(\verb|\headtoname|, \verb|\contentsname|, and so on).  Thus, it's only a matter
+of redefining these ``hooks'' to suit the target language.  However, it would be
+desirable to have some standard definitions set for each language; but
+unfortunately, this cannot be attained just by loading the \babel\ package, for
+two reasons.  In the first place, there are some captions that are specific to
+the \Bundle\ and are therefore not cared for by the \babel\ package: for
+example, the (optional) subject of a letter is preceded by the expansion of
+\verb|\subjectname| (which is ``\emph{Oggetto:}'' in Italian and should be
+``Subject:'' in English), a hook the \babel\ package knows nothing about.
+Secondarily, even for those hooks that are standard, sometimes the definition
+provided by the \babel\ package seems (at least to me) not adequate for a
+letter; in particular, alas, if you load \babel\ with the \opz{italian} option
+(as you ordinarily do when you are writing in Italian), it actually
+\emph{cancels} the definitions preset by the \Bundle, substituting for them
+strings that I~deem more suitable for articles or books, for which they are
+indeed intended, than for letters (for example, \( \verb|\contentsname| \to
+\mbox{``\emph{Indice}''} \) in \babel, instead of \( \verb|\contentsname| \to
+\mbox{``\emph{Sommario}''} \), as defined by the \Bundle; \( \verb|\refname| \to
+\mbox{``\emph{Riferimenti bibliografici}''} \) in \babel, instead of \(
+\verb|\refname| \to \mbox{``\emph{Testi citati}''} \), as I~prefer).
+
+To supply a \emph{provisional} solution to this problem, a new component has
+been added to the \Bundle: the \cdpbabel\ package.  The idea is that, when using
+one of the document classes of the \Bundle, you load the \cdpbabel\ package
+\emph{instead of} \babel, and let the former load the latter on your behalf; in
+this way, you offer it a chance to augment, or amend, the definitions made by
+\babel\ itself.  This solution might seem inelegant (and admittedly it is), but
+the problem is more subtle than it may look at first sight, involving also
+compatibility issues with existing documents, and I~need to further investigate
+it.  It is hoped that a more satisfactory scheme will be found for future
+releases.
+
+In practice, all the \cdpbabel\ package has to do is (to load \babel\ and) to
+issue an \verb|\addto{\captions|\meta{language}\verb|}{|\ldots\verb|}| command
+(or better, one such command for each required \meta{language}), with ``\ldots''
+replaced by the appropriate redefinitions; the list, and the details, of such
+redefintions are of course dictated by \meta{language}, so \cdpbabel\ takes them
+from what we will call a ``C.D.P. language definition file''.  This is a text
+file that, by convention, must be named
+\filedir{cdpnames}\meta{language}\filedir{.ldf}, where \meta{language} is the
+name of the corresponding language option (for example,
+%
+\begin{verbatim}
+    \usepackage[english,italian]{cdpbabel}
+\end{verbatim}
+%
+invokes both \filedir{cdpnamesenglish.ldf} and \filedir{cdpnamesitalian.ldf}, in
+this order), and which must adhere to the format shown in
+listing~\ref{lis:cdpnames}.
+
+%%%%
+\begin{listing}[tbp]
+    \cleantop
+    \zerolistvertspaces
+    \begin{flushleft}
+        \verb|\ProvidesFile{cdpnames|\meta{language}\verb|.ldf}[|%
+                \meta{date \& version}\verb|]|
+    \end{flushleft}
+\begin{verbatim}
+
+\def\@cdpbabel@letter@names{%
+\end{verbatim}
+    \begin{flushleft}
+        \verb|  \def\subjectname      {|\meta{Subject:}\verb|}%|\\
+        \verb|  \def\registeredname   {|\meta{Registered}\verb|}%|\\
+        \verb|  \def\registeredRRname {|\meta{Registered R.R.}\verb|}%|\\
+        \verb|  \def\andccname        {|\meta{cc (in addresses)}\verb|}%|\\
+        \verb|  \def\ccname           {|\meta{cc (at end of letters)}\verb|}%|\\
+        \verb|  \def\enclname         {|\meta{Encl:}\verb|}%|\\
+        \verb|  \def\PSname           {|\meta{P.S.:}\verb|}%|\\
+        \verb|  \def\headtoname       {|\meta{To:}\verb|}%|\\
+        \verb|  \def\lettername       {|\meta{Letter}\verb|}%|
+    \end{flushleft}
+\begin{verbatim}
+  % More captions could be added in the future.
+}
+\def\@cdpbabel@artlet@names{%
+\end{verbatim}
+    \begin{flushleft}
+        \verb|  \def\contentsname     {|\meta{Contents}\verb|}%|\\
+        \verb|  \def\listfigurename   {|\meta{List of figures}\verb|}%|\\
+        \verb|  \def\listtablename    {|\meta{List of tables}\verb|}%|\\
+        \verb|  \def\refname          {|\meta{References}\verb|}%|\\
+        \verb|  \def\indexname        {|\meta{Index}\verb|}%|\\
+        \verb|  \def\figurename       {|\meta{Figure}\verb|}%|\\
+        \verb|  \def\tablename        {|\meta{Table}\verb|}%|\\
+    \end{flushleft}
+\begin{verbatim}
+  % More captions could be added in the future.
+}
+
+\endinput
+\end{verbatim}
+    \caption{Contents of a
+        \filedir{cdpnames}\protect\meta{language}\filedir{.ldf} file}
+    \label{lis:cdpnames}
+    \cleanbot
+\end{listing}
+%%%%
+
+As you can see, a ``C.D.P. language definition file'' must define two macros,
+named \verb|\@cdpbabel@letter@names| and \verb|\@cdpbabel@artlet@names|,
+respectively: in the first you put the redefinitions that should be added to
+\verb|\captions|\meta{language} when only the \lcdp\ class has been loaded; in
+the second you list the additional redefinitions that apply if the \acdp\ class
+is loaded too; and that's all.  Listing~\ref{lis:cdpnames} details exactly what
+hooks need to be redefined when switching to another language; in principle, you
+must supply a suitable redefinition for each of them, but of course, when a hook
+is already defined by the \babel\ package in a way that you think suits, you may
+omit it from your list (or, perhaps better, comment it out).
+
+At present, the \Bundle\ ships with \emph{just two} such definition files
+included: they are \filedir{cdpnamesitalian.ldf}, for Italian, and
+\filedir{cdpnamesenglish.ldf}, for English.  For all other languages, you'll
+have to write and install appropriate files yourself.  Needless to say, you are
+most welcome if, after doing so, you want to contribute your work for inclusion
+in future releases of the \Bundle.  Look at these two provided files, and in
+particular at \filedir{cdpnamesenglish.ldf}, for inspiration about the intended
+meaning of the captions (which sould be quite obvious, however).
+
+
+
+\section{The new \opz{signaturerule} option}
+\label{S:Options}
+
+Some users have asked for a means to add a thin rule in signatures, just above
+the signer's name, to mark the place when the handwritten signature should be
+put.  Although, in my opinion, such usage is highly questionable (only pupils in
+primary school need rules to guide their writing!\@), nevertheless it has now
+been supported.  You request this behavior by passing the new
+\opz{signaturerule} option to the \lcdp\ document class.  Indeed, the decision
+whether to draw the rule or not is a matter of style and, as such, should be
+made, once for all, for the whole document.
+
+Even if you do specify the \opz{signaturerule} option, the rule will \emph{not}
+be drawn inside a \env{signatureenv*} environment, because this environment is
+meant exactly to be used when you are not going to sign the letter by hand.
+This applies also to the \mbox{$*$-form} of the \verb|\closing| and of the
+\verb|\makesignature| commands, which are used for the same purpose and which
+invoke, directly or indirectly, precisely the \env{signatureenv*} environment.
+
+To produce the rule, the \lcdp\ class calls the \verb|\signaturerule| command,
+which you can customize, if you want to, to suit your needs.  This command is
+called in \LaTeX's ``LR~mode'' (or, to be more precise, in \TeX's ``restricted
+horizontal mode''), and it should construct a horizontal box containing the
+rule, aligned along the baseline of the box itself; for example,
+%
+\begin{verbatim}
+    \renewcommand*{\signaturerule}{%
+        \makebox[5cm]{\hrulefill}
+    }
+\end{verbatim}
+%
+could be a typical (re)definition.  The default definition of
+\verb|\signaturerule| is actually like this one, except that it draws a thinner
+rule, and that it allows you to specify the horizontal length of the rule
+(\emph{i.e.}, its width).  Specifically, the \verb|\signaturerulewidth|
+parameter, which is a rigid length, indicates the width of the rule produced by
+the default definition of \verb|\signaturerule|.  Should you ever redefine the
+latter, you should honor this parameter in your redefinition, \emph{e.g.},
+%
+\begin{verbatim}
+    \renewcommand*{\signaturerule}{%
+        \makebox[\signaturerulewidth]{\hrulefill}
+    }
+\end{verbatim}
+%
+But I~think you will hardly need this: most users will content themselves with
+changing the width of the rule.
+
+For completeness' sake, the \opz{nosignaturerule} option is defined too: it is
+the default, and it does not draw the rule.
+
+
+
+\section{Aesthetic adjustments}
+\label{S:Adjustments}
+
+The \verb|\cc| and \verb|\encl| command have been reimplemented in such a way to
+include the ``correct'' interline glue above and below their output.  Remember
+that the output produced by these command is kept on the same page as the
+signature; this means, in particular, that the \verb|\encl| command should be
+used only for very short lists of enclosures (one item or two).  For longer
+lists, utilize the \env{enclosures} environment, which mildly encourages a page
+break above itself.
+
+
+
+\section{A sample letter}
+\label{S:Sample}
+
+Listing~\ref{lis:sample} shows a sample input file that illustrates the features
+covered in this letter: it uses the \packlass{myletter} sample class defined in
+Paragraph~\ref{P:Classes}, with the letterhead drawn by the ``more elaborate''
+version of the \filedir{mylogo.def} file that is reproduced in
+listing~\ref{lis:mylogo-more}, the \opz{signaturerule} option described in
+Section~\ref{S:Options}, and the \verb|\encl| command touched upon in
+Section~\ref{S:Adjustments}.  As before, the output produced by this example is
+shown in a separate letter at the end of this file.
+
+%%%%
+\begin{listing}[tbp]
+    \cleantop
+\begin{verbatim}
+\documentclass
+    [twoside,boldsubject,italicsignature,shortindent,signaturerule]
+    {myletter}
+\usepackage[T1]{fontenc}
+\usepackage[english]{cdpbabel}
+\usepackage{url,lipsum}
+
+\name{Michael Youngster Name}
+\address{
+    Mike Y. \textsc{Name}\\
+    Sails Manager\\
+    \protect\url{m.y.name@my.company.com}
+}
+\signature{Mike Y. Name\\Sails Manager}
+\date{February~8, 2018}
+\place{Mamina del Rey}
+
+\hfuzz = 0pt
+\vfuzz = 0pt
+
+
+
+\begin{document}
+
+\begin{foldedletterhead}[R.~J.~Drofnats]{
+    Revinu~J. \textsc{Drofnats}\\
+    Department of Farm Ecology\\
+    University of St.\,Anford\\
+    Haga Alto, CA~94321
+}[
+    Our new sails.
+]
+
+\opening{Dear affectionate customer:}
+
+we are delighted to have the opportunity of presenting our new
+collection of sails for the incoming yachting season\ldots
+
+\lipsum[1-2]
+
+\closing{Sincerely,}
+
+\encl{2018 Catalogue\\Invitation card}
+
+\end{foldedletterhead}
+
+\end{document}
+\end{verbatim}
+    \caption{A sample input file that uses the new features}
+    \label{lis:sample}
+    \cleanbotp
+\end{listing}
+%%%%
+
+
+
+\epilogue
+
+That, more or less, is all we had to say about version~0.36 of the \Bundle.  For
+further information, write to the author: his e-mail address is on the first
+page.
+
+\closing*{Best regards.}
+
+\PS
+Please note that \packlass{myletter} also used to be (a great many years ago)
+the obsolete name of the \packlass{akletter} document class.  Instructing you to
+create a custom class by that name shouldn't cause you any trouble in
+2018~\facesmile, but I~want to inform you all the same of the potential name
+conflict.
+
+\end{letterhead}
+
+
+
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%                              %
+%       Letter no. 2           %
+%                              %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\begingroup
+
+\date{February~8, 2018}
+
+\begin{customletterhead}{\textwidth}
+    \centering \Huge
+    My Huge Centered Letterhead
+\end{customletterhead}
+\begin{customletterfoot}{\textwidth}
+    \raggedleft \tiny
+    \ruleacrossheadorfoot
+    My (almost unreadable) small print\\
+    flushed against the right margin.
+\end{customletterfoot}
+\setlength\longindentation{.5\textwidth}
+\let \foldingtagrule = \CDPFactoryFoldingTagRule
+
+\begin{foldedletterhead}[Whom it may concern]
+    {To whom it may concern}
+    [My own letterhead, at last!]
+
+\makepresentation
+\maketopdate\relax
+
+\lipsum[1-2]
+
+\makesignature
+
+\end{foldedletterhead}
+
+
+
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%                              %
+%       Letter no. 3           %
+%                              %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\begin{foldedletterhead}[Someone Else]{
+    To Someone Else\\
+    Some other place\\
+    Some other city
+}[
+    Another letterhead.
+]
+
+\begin{customletterhead}{\textwidth}
+    \raggedright \Huge
+    A different head
+\end{customletterhead}
+\begin{customletterfoot}{\textwidth}
+    \centering
+    \ruleacrossheadorfoot
+    A different foot
+\end{customletterfoot}
+
+\opening{Dear Someone,}
+
+\lipsum[1-2]
+
+\closing{Best regards.}
+
+\end{foldedletterhead}
+
+\endgroup
+
+
+
+
+
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%                              %
+%       Letter no. 3           %
+%                              %
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+\begin{foldedletterhead}[R.~J.~Drofnats]{
+    Revinu~J. \textsc{Drofnats}\\
+    Department of Farm Ecology\\
+    University of St.\,Anford\\
+    Haga Alto, CA~94321
+}[
+    Our new sails.
+]
+
+\name{Michael Youngster Name}
+\address{
+    Mike Y. \textsc{Name}\\
+    Sails Manager\\
+    \protect\url{m.y.name@my.company.com}
+}
+\signature{Mike Y. Name\\Sails Manager}
+\date{February~8, 2018}
+\place{Mamina del Rey}
+
+\opening{Dear affectionate customer:}
+
+we are delighted to have the opportunity of presenting our new collection of
+sails for the incoming yachting season\ldots
+
+\lipsum[1-2]
+
+\closing{Sincerely,}
+
+\encl{2018 Catalogue\\Invitation card}
+
+\end{foldedletterhead}
+
+
+\end{document}
diff --git a/macros/latex/contrib/cdpbundl/cdpbundl-doc.pdf b/macros/latex/contrib/cdpbundl/cdpbundl-doc.pdf
new file mode 100644
index 0000000000..de219c9602
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/cdpbundl-doc.pdf
diff --git a/macros/latex/contrib/cdpbundl/cdpbundl.dtx b/macros/latex/contrib/cdpbundl/cdpbundl.dtx
new file mode 100644
index 0000000000..82ac568da6
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/cdpbundl.dtx
@@ -0,0 +1,7746 @@
+% \iffalse
+%   (This is a META-COMMENT.)
+%
+%   This is file `cdpbundl.dtx'.
+%
+%   This file is part of a work named "C.D.P. Bundle".
+%
+%   Copyright (C) 1999-2018 by Gustavo MEZZETTI
+%                             <gustavo.mezzetti@istruzione.it>.
+%
+%   The C.D.P. Bundle may be distributed and/or modified under the
+%   conditions of the LaTeX Project Public License, either version 1.3
+%   of this license or (at your option) any later version.
+%   The latest version of this license is in
+%     http://www.latex-project.org/lppl.txt
+%   and version 1.3 or later is part of all distributions of LaTeX
+%   version 2005/12/01 or later.
+%
+%   The C.D.P. Bundle has the LPPL maintenance status
+%     "author-maintained".
+%
+%   The file `manifest.txt' that comes along with this file specifies
+%   what the C.D.P. Bundle consists of; more precisely, it explains how
+%   the locutions "Work" and "Compiled Work", used in the LaTeX Project
+%   Public License, are to be interpreted in the case of this work.
+%
+%   Note that the distribution of this file alone is "distribution of
+%   only part of the Work" in the sense of the LaTeX Project Public
+%   License, and is not allowed.
+%
+%   (End of the META-COMMENT.)
+% \fi
+%
+% \def\filename{cdpbundl.dtx}
+% \def\fileversion{0.36d}
+% \def\filedate{2018/02/08}
+% \def\docdate {2018/02/08}
+% \def\doclongdate{February~8, 2018}
+%
+% \CheckSum{4989}
+%
+% \DeclareRobustCommand*{\Bundle}{C.D.P. Bundle}
+%
+% \changes{0.30}{2001 Jul 01}{First release of the \Bundle.}
+% \changes{0.31}{2001 Dec 01}{Added support for the \protect\opz{usePS}
+%   option in the \protect\packlass{\protect\cdpaddon} package.}
+% \changes{0.32}{2002 Jul 01}{Removed support for the \protect\opz{usePS}
+%   option in the \protect\packlass{\protect\cdpaddon} package.}
+% \changes{0.33}{2005 Jan 01}{Reorganized code of the
+%   \protect\packlass{\protect\articoletteracdp} class and of the
+%   \protect\packlass{\protect\cdpaddon} package to make it compatible
+%   with the \protect\packlass{\protect\HyperRef} package.}
+% \changes{0.34}{2006 Jan 01}{Improved interaction with the
+%   \protect\packlass{\protect\HyperRef} package.}
+% \changes{0.34}{2006 Jan 01}{Corrected positioning of floats
+%   in float pages.}
+% \changes{0.34}{2006 Jan 01}{Added \texttt{\protect\bslash place} command.}
+% \changes{0.35}{About 2013}{This version was never publicly released, but some 
+%   of the changes listed below for vers.~0.36 were actually introduced in this
+%   version.}
+% \changes{0.36}{2015 Feb 08}{Added \texttt{\protect\bslash OpeningSequence}
+%   command and related macros, in part.\ the \texttt{\protect\bslash
+%   ChosenMakeOpening} hook.}
+% \changes{0.36}{2015 Feb 08}{Added \texttt{\protect\bslash ClosingSequence}
+%   command and related macros, in particular \texttt{\protect\bslash
+%   ChosenMakeClosing} and \texttt{\protect\bslash ChosenMakeSignature}.}
+% \changes{0.36}{2015 Feb 08}{Eventually added functionality to the
+%   \protect\packlass{\protect\cdpaddon} package to support user-defined
+%   letterheads.}
+% \changes{0.36}{2015 Feb 08}{Added \protect\relax the
+%   \protect\opz{signaturerule} option, and its related stuff (the
+%   \texttt{\protect\bslash signaturerule} command, the \texttt{\protect\bslash
+%   signaturerulewidth} parameter), to support rules that mark where to sign by
+%   hand.}
+% \changes{0.36}{2015 Feb 08}{Delegated to a new command
+%   (\texttt{\protect\bslash foldingtagrule}) the task of drawing the sign that
+%   shows where the sheet is to be folded.}
+% \changes{0.36}{2015 Feb 08}{Removed the \protect\packlass{\protect\adiseal}
+%   package and the \protect\packlass{\protect\lettcdpadi} document class.}
+% \changes{0.36}{2015 Feb 08}{Tidied up in several points the code of the
+%   \protect\packlass{\protect\cdpaddon} package.}
+% \changes{0.36}{2015 Feb 08}{Added \protect\packlass{\protect\cdpbabel}
+%   package and related language definition files for English and Italian.}
+%
+%% \CharacterTable
+%%  {Upper-case    \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
+%%   Lower-case    \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
+%%   Digits        \0\1\2\3\4\5\6\7\8\9
+%%   Exclamation   \!     Double quote  \"     Hash (number) \#
+%%   Dollar        \$     Percent       \%     Ampersand     \&
+%%   Acute accent  \'     Left paren    \(     Right paren   \)
+%%   Asterisk      \*     Plus          \+     Comma         \,
+%%   Minus         \-     Point         \.     Solidus       \/
+%%   Colon         \:     Semicolon     \;     Less than     \<
+%%   Equals        \=     Greater than  \>     Question mark \?
+%%   Commercial at \@     Left bracket  \[     Backslash     \\
+%%   Right bracket \]     Circumflex    \^     Underscore    \_
+%%   Grave accent  \`     Left brace    \{     Vertical bar  \|
+%%   Right brace   \}     Tilde         \~}
+%
+% \MakeShortVerb{\"}
+% \DeleteShortVerb{\|}
+%
+% \DoNotIndex{\begin,\end,\def,\let,\else,\fi,\@ifdefinable,\@empty}
+% \DoNotIndex{\newcommand,\renewcommand}
+% \DoNotIndex{\newenvironment,\renewenvironment}
+% \DoNotIndex{\z@,\z@skip,\p@,\@ne,\tw@,\thr@@,\@m,\@M,\m@ne}
+% \DoNotIndex{\setlength,\setcounter,\addtolength}
+% \DoNotIndex{\expandafter,\do,\relax,\advance,\multiply,\divide}
+% \DoNotIndex{\DeclareOption,\ExecuteOptions,\ProcessOptions}
+% \DoNotIndex{\",\.}
+%
+% \IndexPrologue{
+%   \section{\indexname}
+%   Numbers in italics refer to the page where the corresponding entry
+%   is described, the ones underlined to the code line of the
+%   definition, the rest to the code lines where the entry is used.
+% }
+% \setcounter{IndexColumns}{2}
+%
+% \GlossaryPrologue{\section{Change History}}
+% \let \GlossaryParms = \IndexParms
+%
+% \setcounter{StandardModuleDepth}{1}
+%
+% \newcommand*{\DS}{\textsf{DocStrip}}
+% \renewcommand*{\partname}{Part}
+% \newcommand*{\cdpbundl}{cdpbundl}
+% \newcommand*{\letteracdp}{letteracdp}
+% \newcommand*{\articoletteracdp}{articoletteracdp}
+% \newcommand*{\adiseal}{adiseal}
+% \newcommand*{\lettcdpadi}{lettcdpadi}
+% \newcommand*{\cdpaddon}{cdpaddon}
+% \newcommand*{\cdpbabel}{cdpbabel}
+% \newcommand*{\babel}{babel}
+% \newcommand*{\HyperRef}{hyperref}
+% \newcommand*{\pictee}{pict2e}
+% \newcommand*{\epsfig}{epsfig}
+% \newcommand*{\cdpnamesenglish}{cdpnamesenglish.ldf}
+% \newcommand*{\cdpnamesitalian}{cdpnamesitalian.ldf}
+% \newcommand*{\example}{cdpshues-example.def}
+% \newcommand*{\epson}{epson-stylus-740.def}
+% \newcommand*{\hplj}{hp-laserjet-4500.def}
+% \newcommand*{\cdpshues}{cdpshues.cfg}
+% \newcommand*{\textoken}[1]{\(\langle\mbox{\normalfont #1}\rangle\)}
+%
+% \makeatletter
+%
+% \newcounter{paramlist}
+% \renewcommand*{\theparamlist}{^^A
+%   \ifnum \value{paramlist}>\z@
+%     \ifnum \value{paramlist}<10
+%       \arabic{paramlist}^^A
+%     \else
+%       \@ctrerr
+%     \fi
+%   \fi
+% }
+% \newenvironment*{paramlist}{^^A
+%   \setcounter{paramlist}\z@
+%   \@beginparpenalty \@M \relax
+%   \setlength\topsep{\z@}^^A
+%   \tabbing
+%   \(\mbox{\#0}\leftarrow {\,}\)\=\kill
+% }{^^A
+%   \endtabbing
+% }
+% \newcommand*{\param}{^^A
+%   \stepcounter{paramlist}^^A
+%   \(\mbox{\#\theparamlist}\leftarrow{}\)\>^^A
+% }
+% \newcommand*{\myspecialindex}[2]
+%    {\special@index{#1\actualchar#2\encapchar main}}
+%
+% \makeatother
+%
+% \newcommand*{\counterindex}[1]{\myspecialindex{#1}{{\string\ttfamily
+%    \space #1} (counter)}\index{counters:\levelchar{\protect\ttfamily
+%    #1}\encapchar usage}}
+% \newcommand*{\optuseindex}[1]{\SortIndex{#1}{\protect\opz{#1}^^A
+%    (option)\encapchar usage}\index{options:\levelchar
+%    \protect\opz{#1}\encapchar usage}}
+% \newcommand*{\opz}[1]{{\normalfont\ttfamily #1}}
+% \newcommand*{\iopz}[1]{$\mbox{\opz{#1}}\optuseindex{#1}}
+% \newcommand*{\eopz}[1]{\mathbin{|}\mbox{\opz{#1}}\optuseindex{#1}}
+% \newcommand*{\fopz}{$}
+% \newcommand*{\packlass}[1]{{\normalfont\sffamily #1}}
+% \newcommand*{\filedir}[1]{{\normalfont\ttfamily #1}}
+% \newcommand*{\env}[1]{{\normalfont\ttfamily #1}}
+% \newcommand*{\cnt}[1]{{\normalfont\ttfamily #1}}
+% \newcommand*{\sty}[1]{{\normalfont\ttfamily #1}}
+% \newcommand*{\eqref}[1]{(\ref{#1})}
+% \newcommand*{\strongemph}[1]{\textbf{#1}}
+% \newcommand*{\zerolistvertspaces}{^^A
+%   \setlength{\parskip}{0pt}^^A
+%   \setlength{\topsep}{\parskip}^^A
+%   \setlength{\partopsep}{\parskip}^^A
+% }
+% \newcommand*{\closeofsentencespace}{\spacefactor \sfcode `. \space}
+%
+% \DeclareFixedFont{\lhnss}{OT1}{cmss}{m}{n} {12}
+% \DeclareFixedFont{\lhbss}{OT1}{cmss}{m}{n} {17}
+% \DeclareFixedFont{\lhrm} {OT1}{cmr} {m}{n} {9}
+% \DeclareFixedFont{\lhit} {OT1}{cmr} {m}{it}{9}
+% \DeclareFixedFont{\lhtt} {OT1}{cmtt}{m}{n} {9}
+%
+% \providecommand*{\pdfbookmark}[3][]{}
+% \providecommand*{\href}[3][]{#3}
+% \providecommand*{\nolinkurl}[1]{\url{#1}} ^^A if hyperref isn't loades,
+%                                           ^^A hand over to url package
+% \providecommand{\hypersetup}{}
+%
+%
+%
+% \title{
+%    The \Bundle\thanks{This file has version
+%    \fileversion, release date \filedate;
+%    last documentation update: \docdate.
+%    Copyright \copyright~1999--2018 by G.~Mezzetti
+%    (see page~\pageref{S:Copy}).}
+% }
+% \author{G. Mezzetti}
+% \date{\doclongdate}
+%
+% \hypersetup{
+%   pdftitle        = {The C.D.P. Bundle},
+%   pdfauthor       = {G. Mezzetti},
+%   pdfsubject      = {Documentation of the C.D.P. Bundle},
+%   pdfkeywords     = {letter, letterhead},
+%   pdfcreationdate = {D:20180208120000},
+%   pdfmoddate      = {D:20180208120000},
+%   bookmarksopen,
+%   bookmarksopenlevel = 1
+% }
+%
+% \pdfbookmark[0]{Front Matter}{FrontMatter}
+% \maketitle
+%
+% \begin{abstract}
+%    A bundle of \LaTeX\ (former \LaTeXe) classes and packages is
+%    described, which was used by the \emph{Coordinamento dei Dottorandi e
+%    dei Dottori di Ricerca dell'Universit\`{a} di Padova} (a free and
+%    informal association of Ph.D.  students and Ph.D.'s at the
+%    university of Padua, Italy) to write its ``official'' letters.
+%    These classes and packages took care of formatting the letters as
+%    required by the standards of this association; in particular, they
+%    made it very easy to include its seal, both in black-and-white and
+%    in color, at the top of pages.
+% \end{abstract}
+%
+% \tableofcontents
+% \listoffigures
+%
+% \clearpage
+% \begingroup
+%
+%    \setlength{\parskip}{\medskipamount}
+%    \setlength{\parindent}{0pt}
+%
+% \section*{Copyright notice}
+%    \label{S:Copy}
+%    \vspace{-\parskip}
+%
+%    Copyright \copyright~1999--2018 by Gustavo \textsc{Mezzetti}.  All
+%    rights are reserved, except as noted below.
+%
+%    This document has been produced by feeding to a \LaTeX\ typesetting
+%    engine the file \filedir{\filename} version \fileversion\ (\docdate).
+%    This file is part of a work named ``\Bundle''.
+%
+%    The \Bundle\ may be distributed and/or modified under the
+%    conditions of the \LaTeX\ Project Public License, either version~1.3
+%    of this license or (at your option) any later version.  The latest
+%    version of this license is in
+%    \begin{list}{\setlength{\topsep}{0pt}}\item\relax
+%      \ttfamily
+%      http://www.latex-project.org/lppl.txt
+%    \end{list}
+%    and version~1.3 or later is part of all distributions of \LaTeX\
+%    version 2005/12/01 or later.
+%
+%    The \Bundle\ has the LPPL maintenance status ``author-maintained''.
+%
+%    The file \filedir{manifest.txt} included in the \Bundle\ 
+%    specifies what the \Bundle\ consists of; more precisely,
+%    it explains how the locutions ``Work'' and ``Compiled Work'',
+%    used in the \LaTeX\ Project Public License, are to be interpreted
+%    in the case of this work.
+%
+%    Permission is granted to make new printed copies of this document,
+%    by any means (\emph{e.g.}, photocopying, direct printing from the
+%    electronic version, and so on).
+%
+%    Note, though, that distribution of this document alone is
+%    ``distribution of only part of the Work'' in the sense of the
+%    \LaTeX\ Project Public License, and should therefore be avoided:
+%    please distribute, in addition, the source file \filedir{\filename}
+%    together with all other files listed in \filedir{manifest.txt},
+%    as explained in the file \filedir{manifest.txt} itself and also in
+%    Subsection~\ref{sS:License} on page~\pageref{sS:License}, to which you
+%    are referred for more information.
+%
+% \section*{Author's address}
+%    \vspace{-\parskip}
+%
+%    The recommended way to contact the author is by e-mail; his address is:
+%
+%    \begin{list}{\setlength{\topsep}{0pt}}\item\relax
+%      \href{mailto:gustavo.mezzetti@istruzione.it}
+%        {\nolinkurl{gustavo.mezzetti@istruzione.it}}
+%    \end{list}
+%
+%    Please include the \emph{exact} phrase \verb*|C.D.P. Bundle| in the
+%    \emph{subject} of your message; otherwise, your message could be
+%    thrown away by a mail filter.  In this regard, the weakness of the
+%    laws concerning the protection of privacy forces me to explicitly
+%    forbid the use of the above address for any kind of advertising,
+%    marketing, polling, or similar commercial or statistical contact.
+%
+% \endgroup
+%
+%
+%
+% \setcounter{secnumdepth}{0}
+%
+%
+%
+% \clearpage
+% \section{Introduction}
+%
+%    The \emph{Coordinamento dei Dottorandi e dei Dottori di Ricerca
+%    dell'Universit\`a di Padova} (henceforth simply referred to as
+%    ``\emph{Coordinamento}'') was a free association of Ph.D.'s and Ph.D.
+%    students who took their degree, or were studying for it, at the
+%    University of Padova (Padua), Italy.  Discussing its precise nature is
+%    completely outside the scope of this document; the only thing that
+%    concerns us here is that it wrote letters of a somewhat
+%    ``official'' kind, which, for this reason, had to bear its letterhead
+%    on the top of their first page.  The classes and packages herein described 
+%    were used for preparing this kind of letters, automatically taking care of
+%    printing the letterhead; but besides this, they incorporated much more
+%    functionality than the standard \packlass{letter} \LaTeX\ class,
+%    and it was precisely this additional functionality that proved useful
+%    also in more general contexts, thus determining the adoption of the
+%    \Bundle\ in (certain niches of) the \LaTeX\ community.
+%
+%    \subsection{Credits and disclaimer}
+%
+%    The \packlass{\letteracdp} document class was originally based on
+%    the \packlass{letter} standard \LaTeX\ class.  During the time, it
+%    went through so many deep revisions, that by now it retains
+%    practically no relation with the original \packlass{letter} class;
+%    but we want to acknowledge the ``historical'' source anyway.  The
+%    \packlass{\articoletteracdp} document class uses some ideas borrowed
+%    from the \packlass{article} standard \LaTeX\ class.
+%
+%    The author thanks heartfully Alessandro Ambrosi and Roberto
+%    Strepparava, who tested the software and constantly stimulated
+%    improvements and refinements, and Paolo Cojazzi, who, besides this,
+%    also helped with the compression tools.
+%
+%    As usual with computer software, no warranty is given that
+%    this code will work properly, or even that it will work at all.
+%    Using this code can even result in loss of data and/or damages
+%    to your disks and your storage media.
+%    If you use this code, you do so exclusively at your own risk!
+%
+%    See Subsection~\ref{sS:License} and the \LaTeX\ Project Public
+%    License for more information.
+%
+%    \subsection{About this document}
+%
+%    This document, like many documentation files distributed for
+%    \LaTeX, is divided into two parts.
+%
+%    The first part, \emph{User's Manual}, should contain all the
+%    documentation you need to succesfully \emph{use} the classes and
+%    packages that this document presents; but unfortunately (for you!),
+%    this document is still unfinished, so this information is \emph{not}
+%    given here; instead, you are referred to some other sources (all
+%    available through the world-wide web).  The only pieces of
+%    information you will find in this part are how to install those
+%    classes and packages and how to generate this documentation.  This
+%    part, however, specifies to what extent, and under what conditions,
+%    you are allowed to use and distribute the classes and packages
+%    presented in this document.
+%
+%    The second part, \emph{Implementation}, can be omitted if you want
+%    (explanations on how to omit it are given at the beginning of the
+%    part itself), and contains information that concerns only
+%    ``hackers'' who want to learn how the macros that this document
+%    presents are \emph{implemented}.  Actually, this part contains the
+%    complete listing of the \LaTeX\ code that implements the
+%    macros---unfortunately, almost without comments---in the usual \DS\
+%    format; if you are not a \LaTeX\ hacker, this part will not mean
+%    anything to you.
+%
+%    \subsection{About this release: a provisional patch}
+%
+%    The \Bundle\ was essentially written between 1999 and 2000 (for
+%    an Italian audience), and even at that time it contained code that was
+%    already deprecated; even worse, its design was flawed since the
+%    beginning, because it had been conceived for a specific and limited
+%    application (the letters of the C.D.P., exactly), and was adapted for
+%    more general use only as an afterthought.
+%
+%    A thorough redesign would therefore be needed; on the other hand, some
+%    users have suggested, or asked for, improvements and additions, in
+%    particular for what concerns the use of the bundle with other
+%    languages besides Italian, that can be implemented rather easily by
+%    means of provisional patches.  I~have already been deferring the
+%    introduction of these comparatively harmless enhancements for five
+%    years, waiting for the right moment to undertake the task of
+%    redesigning the bundle from scratch, but now I~have resolved to simply 
+%    patch up the existing version.
+%
+%    The macros presented in this document, therefore, are far from being 
+%    optimal: no serious attempt has been made to remove ``fossil'' code, nor 
+%    to bring it up to date with modern \LaTeX\ usage.  The only exception to 
+%    this is a small change that has been made to the fonts used to print the 
+%    letterhead of the \emph{Coordinamento}, switching them from OT1 encoding 
+%    to~T1---because this just required hitting the \meta{DEL} key half a dozen 
+%    of times!~^^A ( paren match
+%    ;-)\closeofsentencespace Of course, nobody will 
+%    care about this, since the least likely reason for which you might want to 
+%    use the \Bundle\ is to produce that letterhead.\footnote{Note, however, 
+%    that the ability to compose the letterhead of the \emph{Coordinamento} is 
+%    still required in order to typeset the documentation given in the 
+%    References.}  For this same 
+%    motive, essentially, I~have also removed the \packlass{\adiseal} package 
+%    and the \packlass{\lettcdpadi} document class, of which, probably, nobody 
+%    besides me even remembers the purpose.
+%
+%    Though\marginpar{\hfill\strongemph{$*{*}*\;$WOW!!$\;*{*}*$}},
+%    ^^A Yes, I know, I should use \textasteriskcentered...
+%    \strongemph{good news} are coming for all those users who asked 
+%    for a means to \strongemph{customize the letterhead} produced by the 
+%    \Bundle: a reasonably viable method for doing so has been provided
+%    at last!~:-D\closeofsentencespace  The method requires the use 
+%    of the \packlass{\cdpaddon} package, passing in the new option 
+%    \opz{customletterhead}.  You specify the contents of your custom head and 
+%    foot by means of two new environments, called \env{customletterhead} and 
+%    \env{customletterfoot}, respectively, which are similar, to a certain 
+%    extent, to the \env{minipage} environment.  This should give you maximum 
+%    freedom in designing the letterhead, whilst adopting an interface you are 
+%    surely well familiar with.
+%    See Subsection~\ref{sS:Customization} for more information.
+%
+%    Another nifty feature is the ability to draw a thin rule to guide your
+%    hand in signing your letters: you ask for this behavior by passing the new
+%    \opz{signaturerule} option to the \packlass{\letteracdp} document class.
+%    See Subsection~\ref{sS:Options} for more information.
+%
+%    Sorry, but for now I~cannot offer any more.
+%
+%    \paragraph*{About version 0.36d.}
+%    It became necessary to release a patch of version~0.36, which has in turn
+%    been given the version number 0.36d, because an awful bug was discovered
+%    that absolutely required correction; I~then took this opportunity to
+%    eliminate as well a few minor errors in the code that I~had noticed
+%    meanwhile.  I~should also mention the fact that the fonts used to print the
+%    letterhead of the \emph{Coordinamento} have been switched back to OT1
+%    encoding (please don't ask why).  Unfortunately, all the remarks set forth
+%    above about the weaknesses in the code design remain valid in this patched
+%    version too.
+%
+%
+%
+% \setcounter{secnumdepth}{3}
+%
+%
+%
+% \clearpage
+% \part{User's Manual}
+%
+% \section{About this part}
+%
+%    We shall only give instructions on how to install the bundle and
+%    how to generate this documentation; partial instructions on how to use
+%    the classes and packages contained in the bundle can be found
+%    in several documents written by the author
+%    \cite{tutti,esempi,etichette,novita,nts,ver028,cdpaddon,ver031,ver036},
+%    but a systematic user's manual is no longer foreseen.~\mbox{:-(}^^A ) match
+%    \closeofsentencespace
+%    Note that including in this document the instructions on how to generate
+%    the document itself may seem pretty useless, but actually isn't:
+%    you might be reading a copy obtained from another person.
+%
+% \section{Installing the \Bundle\ and generating this documentation}
+%
+%    As usual for \LaTeX\ distributions, the \Bundle\ is
+%    distributed in the form of a \filedir{.dtx} file, namely
+%    \filedir{cdpbundl.dtx}, and an accompanying \filedir{.ins} file,
+%    namely \filedir{cdpbundl.ins}.
+%
+%    \subsection{Installation}
+%
+%    To install the bundle, run \LaTeX\ (or plain \TeX) once on the file
+%    \filedir{cdpbundl.ins}.  This will generate the following \LaTeX\
+%    input files:
+%    \begin{quote}
+%      \ttfamily
+%      \articoletteracdp.cls\\
+%      \cdpaddon.sty\\
+%      \cdpbabel.sty\\
+%      \cdpnamesenglish\\
+%      \cdpnamesitalian\\
+%      \example\\
+%      \cdpshues\\
+%      \epson\\
+%      \hplj\\
+%      \letteracdp.cls
+%    \end{quote}
+%    To finish the installation, move them into a \LaTeX\ input
+%    directory.  (If you want, you can discard one, more, or all of the
+%    files whose name ends in \filedir{.def}, each of which contains color
+%    definitions for the seal appropriate for a particular printer.  See
+%    Subsection~\ref{sS:config} for information about how these files
+%    are used for this purpose.) The above listing of all the files you
+%    need to move is also displayed on the terminal at the end of the run
+%    of the file \filedir{cdpbundl.ins}.  The documentation of your \TeX\
+%    installation should tell you how to find the \LaTeX\ input
+%    directory/ies, and probably also how to create new \LaTeX\ input
+%    directories reserved to hold your private classes and packages.
+%
+%    Note that the TDS-compliant directory where the above files should be
+%    put is
+%    \begin{quote}
+%      \texttt{tex/latex/cdpbundl/}
+%    \end{quote}
+%
+%    \subsection{Configuring the \protect\packlass{\cdpaddon} package}
+%    \label{sS:config}
+%
+%    The \packlass{\cdpaddon} package is the part of the \Bundle\ 
+%    that takes care of coloring the C.D.P.  seal, which appears in
+%    black-and-white if you don't load this package.  Experience by trial
+%    and error has shown that some configuration work may be necessary in
+%    order to obtain (more or less) correctly-\null looking colors in the
+%    seal.  This happens because different printers may render color hues
+%    in different ways, sometimes producing surprising results.
+%
+%    The configuration mechanism works as follows.  For each printer
+%    you plan to use there should be a definition file that specifies what
+%    hues should be used to color the C.D.P.  seal.  To select which
+%    file to load, the user indicates its name in an option passed to the
+%    \packlass{\cdpaddon} package.  If the user gives no such indication,
+%    the package reads from a configuration file the name of the default
+%    definition file, and uses that file.  In both cases, if the
+%    designated definition file cannot be read, the package issues a
+%    warning and resorts, for the hues, to an emergency definition
+%    (which, as you can expect, is not very pleasant to the eye).
+%
+%    \subsubsection{Writing color definition files}
+%
+%    The task of a color definition file is simply to define two colors
+%    called "slight@col" and "strong@col" (when the definition file is
+%    read, the "@"~characters are treated as ordinary letters):
+%    "slight@col" is the color used to paint the inner of the D and of
+%    the P in the seal, "strong@col" is the color used to draw the lines.
+%    You define these colors by means of the "\definecolor" command: see
+%    the \textsl{\LaTeX book} \cite[Section~7.3 and
+%    Subsection~C.14.3]{LaTeXbook} for information on colors and the
+%    "\definecolor" command.
+%
+%    The file \filedir{\example}, too, contains comments which explain
+%    how to write new definition files for the \packlass{\cdpaddon}
+%    package.  Indeed, this file is supplied only as a prototype: I suggest
+%    that you write a new file by making a copy of it (with the
+%    appropriate name) and modifying it with the help of the comments.
+%    The colors defined in this file are just an example, and indeed they
+%    are exactly the emergency colors used internally by the
+%    \packlass{\cdpaddon} package when it cannot load a definition
+%    file---that is, a completely useless definition!
+%
+%    The file \filedir{\example} uses the \texttt{named} color model,
+%    but of course you can use any color model you want.  Indeed, it is
+%    best to use ``direct'' color models like \texttt{rgb} or
+%    \texttt{cmyk}, that allow you to drive the printer with precision:
+%    after all, it is exactly for this purpose that you are writing the
+%    file.  The other two definition files included in the \Bundle\ 
+%    illustrate the use of these color models.
+%
+%    \subsubsection{Selecting a color definition file via an option}
+%
+%    The first way to select a particular color definition file among the
+%    ones you have installed is to pass a suitable option to the
+%    \packlass{\cdpaddon} package.  More precisely, the option name has
+%    the form \opz{printer:}\( \langle\textit{bare file name}\rangle \),
+%    all in a row without intervening spaces, where \(
+%    \langle\textit{bare file name}\rangle \) is the name of the
+%    definition file you want to load \emph{without} the extension
+%    \filedir{.def}.  For example, to load a file called
+%    \filedir{acme-wilejet.def}, you pass the option
+%    \opz{printer:acme-wilejet}.  Explicitly, you would write
+%    \begin{verbatim}\usepackage[printer:acme-wilejet]{cdpaddon}\end{verbatim}
+%    to load the \packlass{\cdpaddon} package and the color definitions
+%    suitable for the ACME WileJet printer (the printer preferred by
+%    8~coyotes out of~10).  Similarly, to load the file
+%    \filedir{\example} you would write
+%    \begin{verbatim}\usepackage[printer:cdpshues-example]{cdpaddon}\end{verbatim}
+%    and so on.  Of course, you can still specify, as well, the other
+%    options listed in~\cite{cdpaddon}: for instance,
+%    \begin{verbatim}\usepackage[hypertext,printer:acme-wilejet]{cdpaddon}\end{verbatim}
+%    activates the hyperlinks and selects the colors for the
+%    ACME WileJet printer.
+%
+%    When no \opz{printer:}\ldots\ option is specified, a default
+%    definition file is loaded, as explained in the next section.  For
+%    elegance, you can explicitly request this default definition file with
+%    the \opz{printer:Default} option (note the capitalization).  Of
+%    course, this implies that you cannot have a definition file called
+%    \filedir{Default.def}; but \filedir{default.def} is absolutely OK,
+%    and you can select it with \opz{printer:default}.  Moreover, the
+%    \opz{printer:None} option forces the \packlass{\cdpaddon} package to
+%    ignore the configuration file and to use the emergency, built-in
+%    colors; again, \opz{printer:none}, instead, tries to load a color
+%    definition file called \filedir{none.def}.
+%
+%    \subsubsection{Declaring the default color definition file}
+%
+%    Most users will have only one printer, and even those users who
+%    have access to several printers will use one of them more often than
+%    the others.  Therefore, it is wise to have a second way of selecting
+%    a definition file, to be used when the user does not specify one.
+%    This is done by indicating in a configuration file the name of a
+%    default color definition file.  This configuration file is called
+%    \filedir{\cdpshues}.
+%
+%    The \filedir{\cdpshues} file should contain only zero or one (but
+%    preferably one!) "\DeclareCDPSealHuesDefault" command.  This command
+%    may be used only here, and only once, since it deactivates itself
+%    when executed, and also stops \LaTeX\ from reading any further in
+%    the configuration file.  In its unique (mandatory) argument, one
+%    puts the name, \emph{without} the extension \filedir{.def}, of the
+%    default color definition file.  Do not include any other command in
+%    your configuration file, because the effect of any other command is
+%    undefined.
+%
+%    The \filedir{\cdpshues} file included in the \Bundle\ contains
+%    comments that help you to modify it in order to declare your
+%    personal default color definition file.  The recommended way of
+%    doing this is:
+%    \begin{enumerate}
+%    ^^A ( paren match
+%    \renewcommand*{\labelenumi}{\theenumi)}
+%    \item
+%    make a backup copy (good idea indeed!) of the original configuration
+%    file under a convenient name, for example
+%    \filedir{\cdpshues.original};
+%    \item
+%    modify the \filedir{\cdpshues} file following the advice given
+%    in its comments;
+%    \item
+%    if you want, delete all comments from the (new version of the)
+%    \filedir{\cdpshues} file, to save disk space.
+%    \end{enumerate}
+%
+%    The obsolete version of the \packlass{\cdpaddon} package
+%    documented in~\cite{cdpaddon} was not configurable: it was
+%    programmed to read the color definitions from a file called
+%    \filedir{cdpshues.def}, and this name was hard-coded in the package.
+%    To maintain compatibility with this version, the file
+%    \filedir{\cdpshues} included in the \Bundle\ designates as the
+%    default color definition file exactly a file named
+%    \filedir{cdpshues.def}.  Consequently, if you  install the supplied
+%    files without making any change to them, the \packlass{\cdpaddon}
+%    package will continue to exhibit the old behavior, reading the
+%    legacy \filedir{cdpshues.def} file if you have one installed, and
+%    adopting the emergency colors otherwise.  Note that no actual
+%    \filedir{cdpshues.def} file is included in the \Bundle.
+%
+%    \subsection{Defining the captions for unsupported languages}
+%
+%    Like many other document classes and packages, the classes and
+%    packages of the \Bundle\ mark up some portions of the output they
+%    produce by adding certain descriptive strings, that, by default, are
+%    written in Italian.  For example, when you have requested the
+%    \sty{headings} page style, the name of the addressee, which is printed
+%    atop pages, is preceded by the string ``\emph{A:}'' (=~``To:'');
+%    similarly, when you issue the command "\tableofcontents" in a documents
+%    that adopts the \packlass{\articoletteracdp} document class, the table it
+%    produces is titled ``\emph{Sommario}'' (=~``Contents''); and so on.
+%
+%    When the \Bundle\ was used only by the members of the
+%    \emph{Coordinamento}, the Italian defaults it provided for those captions
+%    were, of course, quite adequate; as long as its use remained circumscribed
+%    to the Italian \LaTeX\ community, they were still acceptable; but now, 
+%    questions about how to adapt the \Bundle\ to foreign languages have 
+%    begun to be asked in some Internet forums by users around the world,
+%    pushing me to reconsider the matter.
+%
+%    Of course, the Italian captions are not (nor they have ever been)
+%    ``hard-wired'' in the code: they are defined by macros that follow the
+%    usual naming conventions ("\headtoname", "\contentsname", and so on).
+%    Thus, it's only a matter of redefining these ``hooks'' to suit the target
+%    language.  However, it would be desirable to have some standard
+%    definitions set for each language; but unfortunately, this cannot be 
+%    attained just by loading the \packlass{\babel} package, for two reasons.
+%    In the first place, there are some captions that are specific to the
+%    \Bundle\ and are therefore not cared for by the \packlass{\babel}
+%    package: for example, the (optional) subject of a letter is preceded by
+%    the expansion of "\subjectname" (which is ``\emph{Oggetto:}'' in Italian
+%    and should be ``Subject:'' in English), a hook the
+%    \packlass{\babel} package knows nothing about.  Secondarily, even for
+%    those hooks that are standard, sometimes the definition provided by the
+%    \packlass{\babel} package seems (at least to me) not adequate for a
+%    letter; in particular, alas, if you load \packlass{\babel} with the
+%    \opz{italian} option (as you ordinarily do when you are writing in
+%    Italian), it actually \emph{cancels} the definitions preset by the
+%    \Bundle, substituting for them strings that I~deem more suitable for
+%    articles or books, for which they are indeed intended, than for letters
+%    (for example, \( "\contentsname" \to \mbox{``\emph{Indice}''} \)
+%    in \packlass{\babel}, instead of
+%    \( "\contentsname" \to \mbox{``\emph{Sommario}''} \), as defined by the
+%    \Bundle;
+%    \( "\refname" \to \mbox{``\emph{Riferimenti bibliografici}''} \) 
+%    in \packlass{\babel},
+%    instead of \( "\refname" \to \mbox{``\emph{Testi citati}''} \), as
+%    I~prefer; etc.).\footnote{I~do not insist on these captions being defined
+%    in the way the \Bundle\ currently uses: if the \LaTeX\  community
+%    thinks that such definitions are inadequate, I~have no objection at all,
+%    of course, to changing them.}
+%
+%    To supply a \emph{provisional} solution to this problem, a new component 
+%    has been added to the \Bundle: the \packlass{\cdpbabel} package.
+%    The idea is that, when using one of the document classes of the
+%    \Bundle, you load the \packlass{\cdpbabel} package \emph{instead of} 
+%    \packlass{\babel}, and let the former load the latter on your behalf;
+%    in this way, you offer it a chance to augment, or amend, the definitions 
+%    made by \packlass{\babel} itself.  This solution might seem inelegant
+%    (and admittedly it is), but the problem is more subtle than it may look
+%    at first sight, involving also compatibility issues with existing
+%    documents, and I~need to further investigate it.  Hopefully, a more
+%    satisfactory  scheme will be found for future releases.\footnote{More
+%    generally, it can be observed that the document classes of the
+%    \Bundle\ rely too heavily on ancillary packages, and that this reconfirms
+%    the ``patched-up'' nature of their design; just think of the entanglement
+%    between the \packlass{\letteracdp} class and the \packlass{\cdpaddon}
+%    package---a typical Italian \emph{pasticcio}, it should be admitted!}
+%
+%    In practice, all the \packlass{\cdpbabel} package has to do is (to load 
+%    \packlass{\babel} and) to issue an 
+%    "\addto{\captions"\meta{language}"}{"\ldots"}" command (or better, 
+%    one such command for each required \meta{language}), with ``\ldots''
+%    replaced by the appropriate redefinitions; the list, and the details,
+%    of such redefintions are of course dictated by \meta{language},
+%    so \packlass{\cdpbabel} takes them from what we will call a ``C.D.P.
+%    language definition file''.  This is a text file that, by convention,
+%    must be named \filedir{cdpnames}\meta{language}\filedir{.ldf},
+%    where \meta{language} is the name of the corresponding language option
+%    (for example,
+%    \begin{verbatim}\usepackage[english,italian]{cdpbabel}\end{verbatim}
+%    invokes both \filedir{\cdpnamesenglish} and  \filedir{\cdpnamesitalian},
+%    in this order), and which must adhere to the format shown
+%    in fig.~\ref{fig:cdpnames}.
+%
+%    \begin{figure}[tbp]
+%      \fontsize{9}{11}\selectfont
+%      \zerolistvertspaces
+%      \begin{flushleft}
+%        "\ProvidesFile{cdpnames"\meta{language}".ldf}["\meta{date \& version}"]"
+%      \end{flushleft}
+%      \begin{verbatim}
+%
+%\def\@cdpbabel@letter@names{%\end{verbatim}
+%      \begin{flushleft}
+%        "  \def\subjectname      {"\meta{Subject:}"}%"\\
+%        "  \def\registeredname   {"\meta{Registered}"}%"\\
+%        "  \def\registeredRRname {"\meta{Registered R.R.}"}%"\\
+%        "  \def\andccname        {"\meta{cc (in addresses)}"}%"\\
+%        "  \def\ccname           {"\meta{cc (at end of letters)}"}%"\\
+%        "  \def\enclname         {"\meta{Encl:}"}%"\\
+%        "  \def\PSname           {"\meta{P.S.:}"}%"\\
+%        "  \def\headtoname       {"\meta{To:}"}%"\\
+%        "  \def\lettername       {"\meta{Letter}"}%"
+%      \end{flushleft}
+%      \begin{verbatim}
+%  % More captions could be added in the future.
+%}
+%\def\@cdpbabel@artlet@names{%\end{verbatim}
+%      \begin{flushleft}
+%        "  \def\contentsname     {"\meta{Contents}"}%"\\
+%        "  \def\listfigurename   {"\meta{List of figures}"}%"\\
+%        "  \def\listtablename    {"\meta{List of tables}"}%"\\
+%        "  \def\refname          {"\meta{References}"}%"\\
+%        "  \def\indexname        {"\meta{Index}"}%"\\
+%        "  \def\figurename       {"\meta{Figure}"}%"\\
+%        "  \def\tablename        {"\meta{Table}"}%"\\
+%      \end{flushleft}
+%      \begin{verbatim}
+%  % More captions could be added in the future.
+%}
+%
+%\endinput\end{verbatim}
+%      \caption{Contents of a 
+%        \protect\filedir{cdpnames}\meta{language}\protect\filedir{.ldf} file}
+%      \label{fig:cdpnames}
+%    \end{figure}
+%
+%    As you can see, a ``C.D.P. language definition file'' must define two 
+%    macros, named "\@cdpbabel@letter@names" and "\@cdpbabel@artlet@names",
+%    respectively: in the first you put the redefinitions that should be
+%    added to "\captions"\meta{language} when only the \packlass{\letteracdp}
+%    class has been loaded; in the second you list the additional redefinitions
+%    that apply if the \packlass{\articoletteracdp} class is loaded too;
+%    and that's all.  The listing shown in fig.~\ref{fig:cdpnames} details exactly
+%    what hooks need to be redefined when switching to another language;
+%    in principle, you must supply a suitable redefinition for each of them,
+%    but of course, when a hook is already defined by the \packlass{\babel}
+%    package in a way that you think suits, you may omit it from your list
+%    (or, perhaps better, comment it out).  Look at the two provided files
+%    for inspiration, and in particular at \filedir{\cdpnamesenglish} for the
+%    intended meaning of the captions (which sould be quite obvious, however).
+%
+%    At present, the \Bundle\ ships with \emph{just two} such definition
+%    files included, namely \filedir{\cdpnamesitalian} for Italian
+%    and \filedir{\cdpnamesenglish} for English: for all other languages,
+%    you'll have to write and install appropriate files yourself.
+%    Needless to say, you are most welcome if, after doing so, you want to
+%    contribute your work for inclusion in future releases of the
+%    \Bundle.  Suggestions for amending the captions specified in the two
+%    existing files are most welcome too; for Italian, it is also a matter of
+%    updating the captions originally defined by the \packlass{\letteracdp}
+%    and \packlass{\articoletteracdp} document classes so that they remain
+%    ``in sync'' with those specified in the \filedir{\cdpnamesitalian} file.
+%
+%    It is hardly worth remarking that ``C.D.P. language definition files''
+%    naturally belong to the same directory where the \Bundle\ is located, 
+%    and \emph{not} to any directory of the \packlass{\babel} system!
+%
+%    One final word of clarification: two of the abovementioned captions,
+%    namely "\ccname"
+%    and "\andccname", look like they are the same, but they actually differ:
+%    the latter is prepended to \emph{addresses} to which the letter is sent
+%    as a ``carbon copy'', whilst the former is used when the names from those
+%    addresses are enumerated again \emph{at the end} of a letter (in the same
+%    place where enclosures are also listed).  In Italian, "\andccname"
+%    should expand to ``\emph{e~p.~c.}'', but "\ccname" just to
+%    ``\emph{P.~c.}''; hence, there is at least one language in which the
+%    distinction is relevant.
+%
+%    \subsection{Documentation}
+%
+%    To produce this documentation, run \LaTeX\ three times (for the
+%    table of contents to be correct) on the file \filedir{\cdpbundl.dtx}.
+%    This won't produce the index and the change history, however: for
+%    those, you have to run MakeIndex on the files \filedir{\cdpbundl.idx}
+%    and \filedir{\cdpbundl.glo}, produced during the previous \LaTeX\
+%    run, with the styles \filedir{gind.ist} and \filedir{gglo.ist},
+%    respectively (these styles are part of the standard \LaTeX\
+%    distribution); then pass \filedir{\cdpbundl.dtx} through \LaTeX\
+%    twice more.
+%
+%    Starting with version 0.36 of the \Bundle, a (quite trivial!\@) makefile
+%    that ``knows'' how to produce the documentation is offered along with the 
+%    Bundle itself.  Although it is not a required part of the distribution
+%    (as per LPPL\@), you may find that some distributors supply it all the
+%    same (I~hope the CTAN\@ sites will do so).  With this makefile in the same 
+%    directory as \filedir{\filename}, the shell command
+%    \begin{quote}
+%      \ttfamily
+%      make doc
+%    \end{quote}
+%    will take all the necessary actions to produce the full documentation
+%    (in PDF\@; the modifications you need to introduce into the makefile
+%    in order to obtain DVI\@ output should be quite obvious, however).
+%
+%    The same makefile can also be used to extract the various class, package,
+%    and ancillary (definition and configuration) files: simply issue the
+%    command
+%    \begin{quote}
+%      \ttfamily
+%      make code
+%    \end{quote}
+%    at the shell prompt; whereas
+%    \begin{quote}
+%      \ttfamily
+%      make
+%    \end{quote}
+%    will \emph{both} extract the code files \emph{and} typeset the
+%    documentation.  Type
+%    \begin{quote}
+%      \ttfamily
+%      make help
+%    \end{quote}
+%    for more information.
+%
+% \section{How to use the \Bundle}
+%
+%    The \Bundle\ v.~0.36 contains two \LaTeX\ document classes,
+%    namely \packlass{\letteracdp} and \packlass{\articoletteracdp},
+%    and two helper \LaTeX\ packages, called \packlass{\cdpaddon}
+%    and \packlass{\cdpbabel}, plus a certain number of definition
+%    and configuration files related to these packages.
+%    As already said, the actual purpose of this section is not
+%    to explain you how to use these macro files, but only to give you
+%    references to documents where you can find the explanations.
+%
+%    For instructions on how to use the \packlass{\letteracdp} class
+%    the reader is referred to \cite{tutti,esempi,etichette,nts,ver028,ver031}.
+%    Note, however, that the class is syntactically compatible with the
+%    \packlass{letter} standard \LaTeX\ class, in the sense that a
+%    document prepared for the \packlass{letter} class can be compiled
+%    without errors with the \packlass{\letteracdp} class; but the output
+%    will be different.
+%
+%    As a minimal reference, fig.~\ref{fig:input} illustrates the typical
+%    structure of a simple input file for the \packlass{\letteracdp}
+%    document class.
+%
+% \iffalse
+%   Meta-comment: a <*gobble> guard is needed here to prevent the
+%   DocStrip program from putting the lines beginning with "%%" in the
+%   generated files.
+%<*gobble>
+% \fi
+%    \begin{figure}[tbp]
+%      \zerolistvertspaces
+%      \begin{verbatim}\documentclass[boldsubject,italicsignature,smartindent]{letteracdp}
+%% Of course, the above options are a matter of personal taste...
+%\usepackage[T1]{fontenc} % as it is now customary
+%% Since we are writing in English, we need to redefine some captions;
+%% the following package automatically takes care of this:
+%\usepackage[english]{cdpbabel}
+%% Presently only two languages are supported: "english" and "italian".
+%
+%% Name, address and signature of the sender (the name is optional):
+%\name{Revinu Jitis Drofnats}
+%\address{
+%    Revinu~J. \textsc{Drofnats}\\
+%    Department of Farm Ecology\\
+%    University of St.\,Anford\\
+%    Haga Alto, CA~94321 (U.S.A.)
+%}
+%\signature{R.~J. Drofnats\\Professor}
+%\date{February~8, 2018} % as usual, date is optional, default is \today
+%\place{St.\,Anford}     % place where the letter is written (optional)
+%
+%% Uncomment the following declaration if you want running heads:
+%% \pagestyle{headings}
+%
+%
+%
+%\begin{document}
+%
+%\begin{letterhead}[Brian~K. Reid]{
+%    Prof.~Brian~K. \textsc{Reid}\\
+%    Department of Electrical Engineering\\
+%    Stanford University\\
+%    Stanford, CA~94305 (U.S.A.)
+%}[
+%    This is the optional subject of the letter.
+%]
+%
+%\opening{Dear Prof.~Reid,}
+%
+%this letter is typeset using a \texttt{letterhead} environment, so it
+%will be printed with the letterhead of the \emph{Coordinamento} above
+%it; if you don't want it, use the \texttt{letter} environment instead.
+%You can also use the \texttt{foldedletterhead} environment in place
+%of the \texttt{letterhead} environment (or \texttt{foldedletter} in
+%place of \texttt{letter}) to obtain a letter prepared to be folded in
+%three parts, as one usually does before putting it in an envelope.
+%Experiment to see what happens.
+%
+%\closing{Sincerely,}
+%
+%\end{letterhead}
+%
+%\end{document}\end{verbatim}
+%      \caption{A sample input file for the \protect\packlass{\letteracdp}
+%        document class}
+%      \label{fig:input}
+%    \end{figure}
+% \iffalse
+%</gobble>
+% \fi
+%
+%    For instructions on how to use the \packlass{\articoletteracdp}
+%    class, see~\cite{novita}.
+%
+%    For instructions on how to use the \packlass{\cdpaddon} package,
+%    see~\cite{cdpaddon}.  Note, however, that this document describes an
+%    obsolete version, which lacks the ability to deal with several color
+%    definition files.  The use of the \packlass{\cdpaddon} package for 
+%    customizing the letterhead, though, is covered in~\cite{ver036}.
+%
+%    For instructions on how to use the \packlass{\cdpbabel} package,
+%    see~\cite{ver036}.
+%
+%    Please note that before using the \Bundle\ you must read the
+%    following license to see whether its terms are acceptable for you,
+%    especially for what concerns the lack of any warranty; if they are
+%    not, don't use this program.
+%
+%    \subsection{License}
+%    \label{sS:License}
+%
+%    The \Bundle\ is \emph{not} in the public domain: its author,
+%    Gustavo \textsc{Mezzetti}, owns the copyright, and in general retains
+%    all the rights therein; but as a special exception, the author
+%    grants you the permissions indicated below.
+%
+%    \subsubsection{Distribution and/or modification}
+%
+%    The \Bundle\ may be distributed and/or modified under the
+%    conditions of the \LaTeX\ Project Public License, either version~1.3
+%    of this license or (at your option) any later version.  The latest
+%    version of this license is in
+%    \begin{quote}
+%      \ttfamily
+%      http://www.latex-project.org/lppl.txt
+%    \end{quote}
+%    and version~1.3 or later is part of all distributions of \LaTeX\
+%    version 2005/12/01 or later.
+%
+%    The \Bundle\ has the LPPL maintenance status ``author-maintained''.
+%
+%    The file \filedir{manifest.txt} included in the \Bundle\ 
+%    specifies what the \Bundle\ consists of; more precisely,
+%    it explains how the locutions ``Work'' and ``Compiled Work'',
+%    used in the \LaTeX\ Project Public License, are to be interpreted
+%    in the case of this work.
+%
+%    \subsubsection{Use}
+%
+%    The use of the \Bundle\ is unrestricted, provided that you
+%    accept the terms and conditions of the \LaTeX\ Project Public
+%    License and of the following subsection for what concerns the absence
+%    of any warranty.
+%
+%    \subsubsection{No warranty}
+%
+%    There is absolutely no warranty for the \Bundle.  The
+%    Copyright Holder provides the \Bundle\ ``as is'', without
+%    warranty of any kind, either expressed or implied, including, but
+%    not limited to, the implied warranties of merchantability and
+%    fitness for a particular purpose.  The entire risk as to the quality
+%    and performance of the \Bundle\ is with you.  Should the
+%    \Bundle\ prove defective, you assume the cost of all necessary
+%    servicing, repair, or correction.
+%
+%    In no event will The Copyright Holder, or any other party who may
+%    distribute and/or modify the \Bundle\ as permitted by the
+%    \LaTeX\ Project Public License, be liable to you for damages,
+%    including any general, special, incidental or consequential damages
+%    arising out of any use of the \Bundle\ or out of inability to
+%    use it (including, but not limited to, loss of data, data being
+%    rendered inaccurate, or losses sustained by anyone as a result of any
+%    failure of the \Bundle\ to operate with any other programs),
+%    even if The Copyright Holder or said other party has been advised of
+%    the possibility of such damages.
+%
+%    \subsection{Options of the \protect\packlass{\letteracdp} class}
+%    \label{sS:Options}
+%
+%    Of course, you load the \packlass{\letteracdp} class by means of the
+%    usual "\documentclass" declaration, which allows you to specify
+%    various options.  For some reason, the complete list of all the
+%    options recognized by this class has never been given in any of the
+%    previous documents containing instructions about it; so, we give it
+%    here.
+%
+%    We shall now list all the options recognized by the
+%    \packlass{\letteracdp} class, including the standard ones it can
+%    understand.  If an option does not appear in the list given below,
+%    then that option is not recognized by the \packlass{\letteracdp}
+%    class, even if it is a standard one (that is, documented in the
+%    \textsl{\LaTeX book}~\cite{LaTeXbook}).
+%
+%    We begin with the list of standard options.  Since they are
+%    already described in the \textsl{\LaTeX book}~\cite{LaTeXbook}, we
+%    describe only the options that behave differently from the standard;
+%    the others are just listed without description.
+%
+%    \begin{description}
+%
+%    \item[\iopz{10pt}\eopz{11pt}\eopz{12pt}\fopz]
+%
+%    \item[\iopz{letterpaper}\eopz{legalpaper}\eopz{executivepaper}\eopz
+%      {a4paper}\eopz{a5paper}\eopz{b5paper}\fopz]
+%    \hfil\null\linebreak
+%    Note that \packlass{\letteracdp} uses \opz{a4paper} as the default.
+%
+%    \item[\iopz{landscape}\fopz]
+%
+%    \item[\iopz{final}\eopz{draft}\fopz]
+%
+%    \item[\iopz{oneside}\eopz{twoside}\fopz]
+%
+%    \item[\iopz{onecolumn}\eopz{twocolumn}\fopz] The \opz{twocolumn}
+%    option is recognized, but triggers an error; the \opz{onecolumn}
+%    option is recognized, but it is ignored because in any case the
+%    document is typeset in one-column mode.  Note, however, that
+%    requesting \opz{onecolumn} as a global option could make sense:
+%    precisely, it could serve to inform possible packages that the
+%    document has only one column.  But, precisely for this reason, this
+%    option is requested by default during the class initialization;
+%    there is hence no reason to specify it, but it does no harm.
+%
+%    \item[\iopz{leqn}\fopz]
+%
+%    \item[\iopz{fleqn}\fopz]
+%
+%    \end{description}
+%
+%    We now list the option specific to the \packlass{\letteracdp} class.
+%
+%    \begin{description}
+%
+%    \item[\iopz{mediumsubject}\eopz{boldsubject}\fopz]
+%    The \opz{mediumsubject} option requests that the subject of the
+%    letters be typeset in medium weight, while the \opz{boldsubject}
+%    option makes it appear in boldface type.  The default is
+%    \opz{mediumsubject}.
+%
+%    \item[\iopz{uprightsignature}\eopz{italicsignature}\fopz]
+%    The \opz{uprightsignature} option requests that the signature of the
+%    letters be typeset in upright shape, while the \opz{italicsignature}
+%    option makes it appear in italic shape.  The default is
+%    \opz{uprightsignature}.
+%
+%    \item[\iopz{signaturerule}\eopz{nosignaturerule}\fopz]
+%    Drawing or not a thin rule to mark the spot where you should sign a
+%    letter is a matter of style that, as such, should apply to the whole
+%    document; for this reason, this behavior is requested by menas of an
+%    option, namely \opz{signaturerule}.  As you can guess, \opz{signaturerule}
+%    causes the rule to be drawn, while \opz{nosignaturerule}, which is defined
+%    for the sake of completeness, suppresses it.  Anyway, the rule is never
+%    drawn inside a \env{signatureenv*} environment; this includes signatures
+%    generated by the \mbox{$*$-form} of the "\closing" command.
+%    You can adjust the width of the rule by modifying, with "\setlength",
+%    the "\signaturerulewidth" rigid length.
+%
+%    \item[\iopz{noPS}\eopz{usePS}\fopz]
+%    These two options are obsolete (to say the least!\@) and should
+%    \emph{not} be used any longer.  If you want to improve the graphical
+%    quality of the seal, simply load the \packlass{\pictee} package in
+%    your document, along with the \packlass{\cdpaddon} package (of course, 
+%    if you do so, PostScript or PDF\@ printing will be needed to produce the 
+%    output).
+%
+%    \item[\iopz{indent}\eopz{noindent}\eopz{smartindent}\eopz{shortindent}\fopz]
+%    These options are used to specify the paragraph indentation, but
+%    only for letters; any portion of text that is not included in a
+%    letter---but normally there is no such text---is not affected by
+%    these options.  The \opz{indent} option sets the paragraph
+%    indentation, for letters, to one tenth of the text width,
+%    unless this amount looks too bad, in which case the indentation
+%    is set to 2~picas.  The \opz{noindent} option completely
+%    suppressess paragraph indentation within letters.  The \opz{smartindent}
+%    option sets the paragraph indentation, for letters, to the width
+%    of (the last line of) the salutation, unless this amount looks
+%    too bad, in which case it behaves like \opz{indent}.  The \opz{shortindent}
+%    option maintains also for letters the same indentation used for
+%    text not included in letters (see below); its name, chosen to be
+%    more easily remembered, is due to the fact that normally it involves
+%    a shorter indentation than the default one.  The default is \opz{indent}.
+%    I repeat that these options do not affect any text that should appear
+%    outside of letters, whose paragraphs will be always indented by
+%    2~em, where the unit of 1~em is taken from the main document font;
+%    this is also the paragraph indentation for letters if the
+%    \opz{shortindent} option is specified.  Paragraphs of
+%    postscripts are never indented.
+%
+%    \item[\iopz{105x37labels}\eopz{70x37labels}\eopz{Avery5352labels}\fopz]
+%    These options indicate the format of the address labels.  The
+%    first two options indicate address labels of mm~105\,$\times$\,37
+%    and mm~70\,$\times$\,37, respectively.  The third option
+%    indicates the address labels used by the standard \packlass{letter}
+%    class.  Note the uppercase letter in \opz{Avery5352labels}.  The
+%    default is \opz{105x37labels}.
+%
+%    \end{description}
+%
+%    \subsection{Customizing the letterhead}
+%    \label{sS:Customization}
+%
+%    A new, long-awaited feature is available at last: it is now possible, 
+%    with reasonable ease, to customize the letterhead produced by the
+%    \env{letterhead} environment.~:-D\closeofsentencespace
+%    As a matter of fact, this customization has always been possible---the
+%    \env{letterhead} environment would have been completely useless
+%    otherwise---but instructions on how to carry it out were given uniquely
+%    in documents that were only privately circulated; moreover, these
+%    instructions required you to modify some of the internal commands of the
+%    \Bundle.  What the present version does is to provide a reasonable user
+%    interface for making these internal changes and (which is not less
+%    important) to document this interface.
+%
+%    The customization of the letterhead basically involves the following three
+%    steps:
+%
+%    \begin{enumerate}
+%
+%    \item
+%    First of all, you need to load the \packlass{\cdpaddon} package,
+%    which is part of the \Bundle, passing to it the (new) option
+%    \opz{customletterhead}.
+%
+%    \item
+%    The \packlass{\cdpaddon} package defines two environments, named
+%    \env{customletterhead} and \env{customletterfoot}, respectively,
+%    that can be used more or less like a \env{minipage} environment.
+%    You should put, in any place before the first letter (not entirely exact,
+%    but almost so: we'll refine this information underneath), a
+%    \env{customletterhead} environment holding the
+%    description of your letterhead.  Just pretend you are composing a
+%    \env{minipage} with your letterhead inside.
+%
+%    \item
+%    If you also want to customize the page footer (as it is ordinarily the
+%    case), define its contents inside a similarly placed
+%    \env{customletterfoot} environment.
+%    If you omit this step, the footer will be empty.
+%
+%    \end{enumerate}
+%
+%    \DescribeEnv{customletterhead}^^A
+%    \DescribeEnv{customletterfoot}^^A
+%    More formally, the \packlass{\cdpaddon} package makes two new environments
+%    available, named as stated above, that conform to the following syntax:
+%
+%    \begin{flushleft}
+%      "\begin{customletterhead}{"\meta{wdth}"}"\quad
+%        \meta{text}\quad
+%      "\end{customletterhead}"\\
+%      "\begin{customletterfoot}{"\meta{wdth}"}"\quad
+%        \meta{text}\quad
+%      "\end{customletterfoot}"
+%    \end{flushleft}
+%
+%    Both these environments typeset \meta{text} in a \env{minipage} with
+%    width \meta{wdth} and save the result in a box register specifically
+%    reserved for this purpose (each environment has its own, dedicated
+%    register); subsequently, if the \opz{customletterhead} option has been
+%    specified, the contents of these box registers are used in place of the
+%    header and footer ordinarily defined by the \packlass{\letteracdp}
+%    document class.  Note that the \packlass{\cdpaddon} package defines the
+%    \env{customletterhead} and \env{customletterfoot} environments in any
+%    case, \emph{independently} of which options you pass to it.
+%
+%    The contents specified inside \env{customletterhead} and
+%    \env{customletterfoot} will be horizontally centered in the header and
+%    footer boxes, respectively; these boxes are defined by the page layout,
+%    but normally their left and right edges coincide with those of the main
+%    text.  If the \meta{wdth} you have specified for the contents themselves
+%    exceeds the width available in the header\slash footer, they will stick
+%    out by the same amount of space on both sides (in brief: the contents are
+%    centered with "\hss" at both ends).  Normally, you pass "\textwidth" as
+%    the \meta{wdth} parameter\footnote{I~have long been in doubt whether to make
+%    \meta{wdth} an optional parameter, with default value equal to
+%    \texttt{\bslash textwidth}; eventually, I~decided for a syntax that
+%    parallels the syntax of the \env{minipage} environment, and should
+%    therefore be obvious to remember.} and align things as you prefer
+%    \emph{inside} the \env{minipage}, perhaps creating sub-boxes or using 
+%    \env{picture}s.
+%
+%    Coming to vertical alignment, the boxes produced by the
+%    \env{customletterhead}\slash\env{customletterfoot} environments are
+%    ``smashed'' down to null height and depth;
+%    for \env{customletterhead}, the bottom edge of the box
+%    is aligned with the baseline of the header, whilst for
+%    \env{customletterfoot} it is the top edge which is aligned
+%    with the baseline of the footer.  If you want the contents of
+%    \env{customletterhead} to sink below the baseline of the header,
+%    simply backspace vertically at their end, \emph{i.e.},
+%    use "\vspace{"\meta{dist}"}" with a negative \meta{dist},
+%    and the bottom edge of your custom header will be placed exactly
+%    \( \left|\meta{dist}\right| \) below the baseline of the header
+%    as defined by the general page layout.
+%    Similarly, a "\vspace{"\meta{dist}"}" with a negative \meta{dist}
+%    placed at the beginning of your custom footer will rise its top edge
+%    exactly \( \left|\meta{dist}\right| \) above the baseline of the footer
+%    defined by the general page layout.
+%
+% \iffalse
+%   Meta-comment: a <*gobble> guard is needed here to prevent the
+%   DocStrip program from putting the lines beginning with "%%" in the
+%   generated files.
+%<*gobble>
+% \fi
+%    \begin{figure}[tbp]
+%      \zerolistvertspaces
+%      \begin{verbatim}\documentclass
+%    [twoside,boldsubject,italicsignature,shortindent,signaturerule]
+%    {letteracdp}[2015/01/20]
+%\usepackage[T1]{fontenc}
+%\usepackage[english]{cdpbabel}
+%\usepackage[customletterhead]{cdpaddon}[2015/01/21]
+%\usepackage{url,lipsum}
+% 
+%\address{
+%    Gustavo \textsc{Mezzetti}\\
+%    \protect\url{gustavo.mezzetti@istruzione.it}
+%}
+%\signature{Gustavo Mezzetti}
+%\date{February~8, 2018}
+%\place{Padova}
+%
+%
+%
+%% Definition of your letterhead occurs here:
+%
+%\begin{customletterhead}{\textwidth}
+%    \centering \Huge
+%    My Huge Centered Letterhead
+%\end{customletterhead}
+%\begin{customletterfoot}{\textwidth}
+%    \raggedleft \tiny
+%    \ruleacrossheadorfoot
+%    My (almost unreadable) small print\\
+%    flushed against the right margin.
+%\end{customletterfoot}
+%
+%
+%
+%\begin{document}
+%
+%\begin{foldedletterhead}[Whom it may concern]
+%    {To whom it may concern}
+%    [My own letterhead, at last!]
+%
+%\makepresentation
+%\maketopdate\relax
+%
+%\lipsum[1-2]
+%
+%\makesignature
+%
+%\end{foldedletterhead}
+%
+%\end{document}\end{verbatim}
+%      \caption{How to customize the letterhead}
+%      \label{fig:customletter}
+%    \end{figure}
+% \iffalse
+%</gobble>
+% \fi
+%
+%    Fig.~\ref{fig:customletter} shows a sample input file for a letter with
+%    customized letterhead.  Note that, among the others, we load the
+%    \packlass{\cdpaddon} package with the \opz{customletterhead} option.
+%    Note also that the \env{customletterhead}\slash\env{customletterfoot}
+%    environments \emph{can} be placed in the preamble; this makes it very easy
+%    to create a definition file containing the description of your custom
+%    letterhead, to be subsequently loaded in your source files,
+%    or even to define your custom version of the \packlass{\letteracdp}
+%    and \packlass{\articoletteracdp} document classes.  For example, the three
+%    files \filedir{myletter.cls}, \filedir{myarticletter.cls}, and
+%    \filedir{mylogo.def}, whose contents are listed in
+%    fig.~\ref{fig:myletter}, \ref{fig:myarticletter}, and~\ref{fig:mylogo},
+%    respectively, together define two new classes, called \packlass{myletter}
+%    and \packlass{myarticletter}, that respectively parallel
+%    \packlass{\letteracdp} and \packlass{\articoletteracdp}, but produce the
+%    same letterhead as the file of 
+%    fig.~\ref{fig:customletter}.\footnote{Please note that \packlass{myletter} 
+%    also used to be (a great many years ago) the obsolete name of the 
+%    \packlass{akletter} document class.  Instructing you to create a custom 
+%    class by that name shouldn't cause you any trouble in
+%    ^^A ( paren match
+%    2018~:-), but I~want to inform you all the same of the potential name 
+%    conflict.}
+%
+%    \begin{figure}[tbp]
+%      \zerolistvertspaces
+%      \begin{verbatim}\NeedsTeXFormat{LaTeX2e} % LaTeX2e is required!
+%\ProvidesClass{myletter}
+%              [2018/02/08 v0.01 (development)]
+%\LoadClassWithOptions{letteracdp}[2015/01/20]
+%\input{mylogo.def}
+%\endinput\end{verbatim}
+%      \caption{Contents of the \protect\filedir{myletter.cls} file}
+%      \label{fig:myletter}
+%    \end{figure}
+%
+%    \begin{figure}[tbp]
+%      \zerolistvertspaces
+%      \begin{verbatim}\NeedsTeXFormat{LaTeX2e} % LaTeX2e is required!
+%\ProvidesClass{myarticletter}
+%              [2018/02/08 v0.01 (development)]
+%\LoadClassWithOptions{articoletteracdp}[2015/01/20]
+%\input{mylogo.def}
+%\endinput\end{verbatim}
+%      \caption{Contents of the \protect\filedir{myarticletter.cls} file}
+%      \label{fig:myarticletter}
+%    \end{figure}
+%
+%    \begin{figure}[tbp]
+%      \zerolistvertspaces
+%      \begin{verbatim}\ProvidesFile{mylogo.def}[2018/02/08 v0.01 (development)]
+%
+%\RequirePackage[customletterhead]{cdpaddon}[2015/01/21]
+%
+%\begin{customletterhead}{\textwidth}
+%    \centering \Huge
+%    My Huge Centered Letterhead
+%\end{customletterhead}
+%\begin{customletterfoot}{\textwidth}
+%    \raggedleft \tiny
+%    \ruleacrossheadorfoot
+%    My (almost unreadable) small print\\
+%    flushed against the right margin.
+%\end{customletterfoot}
+%
+%\endinput\end{verbatim}
+%      \caption{Contents of the \protect\filedir{mylogo.def} file}
+%      \label{fig:mylogo}
+%    \end{figure}
+%
+%    One final word: the \env{customletterhead}\slash\env{customletterfoot}
+%    environments save their contents in their respective box registers by
+%    means of a \emph{local} assignment, subject to ordinary scoping rules:
+%    this can be useful if you want to change the letterhead for just a single
+%    letter in a source file that contains many ones.
+%
+%    See~\cite{ver036} for more information.
+%
+% \StopEventually{
+%    \setcounter{secnumdepth}{0}
+%    \providecommand*\bysame{\leavevmode\hbox to3em{\hrulefill}\thinspace}
+%
+%    \clearpage
+%    \pdfbookmark[0]{Back Matter}{BackMatter}
+%    \begin{thebibliography}{99}
+%    \addcontentsline{toc}{section}{\refname}
+%
+%    \bibitem{LaTeXbook}
+%    L.~Lamport, \emph{\LaTeX---A Document Preparation System---User's
+%       Guide and Reference Manual}, 2nd~edition, Addison-Wesley,
+%       Reading, 1994.
+%
+%    \bibitem{tutti}
+%    G.~Mezzetti, \emph{Breve presentazione d'una classe \LaTeX, denominata
+%       \packlass{\letteracdp}, utile nella preparazione delle lettere del
+%       Coordinamento}, technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/presentazione.tex}}
+%
+%    \bibitem{esempi}
+%    \bysame, \emph{Esempi d'uso della classe \packlass{\letteracdp}},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/esempi.tex}}
+%
+%    \bibitem{etichette}
+%    \bysame, \emph{Etichette degli indirizzi con la classe \packlass{\letteracdp}},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/etichett.tex}}
+%
+%    \bibitem{novita}
+%    \bysame, \emph{Grandi novit\`{a} per \packlass{\letteracdp}:
+%       arriva \packlass{\articoletteracdp}!}, technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/novita.tex}}
+%
+%    \bibitem{nts}
+%    \bysame, \emph{Forse non tutti sanno che\ldots},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/nontuttisanno.tex}}
+%
+%    \bibitem{ver028}
+%    \bysame, \emph{Annuncio delle versioni 0.28 della classe \packlass{\letteracdp}
+%       e 0.08 della classe \packlass{\articoletteracdp}},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/ver0-28.tex}}
+%
+%    \bibitem{cdpaddon}
+%    \bysame, \emph{Il pacchetto \packlass{\cdpaddon}},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/cdpaddonistr.tex}}
+%
+%    \bibitem{ver031}
+%    \bysame, \emph{Annuncio della versione 0.31 del \emph{\Bundle}},
+%       technical note downloadable from:\\
+%       \rlap{\url{http://www.math.unipd.it/~mezzetti/Gustavo/Ludic/CDP/ver0-31.tex}}
+%
+%    \bibitem{ver036}
+%    \bysame, \emph{The \Bundle\ version~0.36},
+%      included in the documentation of the \packlass{\cdpbundl} package,\\
+%      \href{file:cdp-ver-0-36.pdf}
+%        {\nolinkurl{$TEXMF/doc/latex/cdpbundl/cdp-ver-0-36.pdf}}
+%
+%    \end{thebibliography}
+% }
+%
+%
+%
+% \clearpage
+% \part{Implementation}
+%
+% \changes{0.36a-c}{Between 2015 and 2018}{Never publicly released.}
+%
+% \section{About this part}
+%
+%    This part is of interest only to \LaTeX\ hackers; to avoid
+%    having this part printed, look in the file \filedir{\filename}
+%    for a line that looks \emph{exactly} like this
+%    \begin{verbatim}%% \OnlyDescription % uncomment to discard Implementation part\end{verbatim}
+%    and remove the two leading percent signs ("%%").
+%
+% \section{A driver for this document}
+%
+%    This part of the file is \emph{not} included in any generated file:
+%    it is simply the driver.
+%    \begin{macrocode}
+%<*driver>
+%    \end{macrocode}
+%
+%    To begin with, we load the \packlass{ltxdoc} class and the 
+%    \packlass{hypdoc} package.
+%    \begin{macrocode}
+\documentclass{ltxdoc}
+\usepackage{hypdoc}
+%    \end{macrocode}
+%    We now set a few typesetting options.
+%    First of all, we want a history listing and a full index, the latter
+%    organized by line numbers.
+%    \begin{macrocode}
+\RecordChanges
+\EnableCrossrefs
+\CodelineIndex
+%    \end{macrocode}
+%    If you don't want to include the second part of this document,
+%    \emph{Implementation}, uncomment the line containing the command
+%    "\OnlyDescription".
+%    \begin{macrocode}
+%% \OnlyDescription % uncomment to discard Implementation part
+%    \end{macrocode}
+%    Finally, setting "\hfuzz" and "\vfuzz" to 0~points is only one
+%    of the many neurotic symptoms of the author!
+%    \begin{macrocode}
+\hfuzz = 0pt
+\vfuzz = 0pt
+%    \end{macrocode}
+%    Now input this same file, using \DS\ conventions.
+%    \begin{macrocode}
+\begin{document}
+  \DocInput{cdpbundl.dtx}
+%    \end{macrocode}
+%    Then print the change list and the index.  We put these commands in
+%    the driver, rather than in the comments of this file, because
+%    producing the change list and the index is somewhat cumbersome, and some
+%    users could prefer to omit them: such users should simply use a
+%    different driver.
+%    \begin{macrocode}
+  \clearpage \PrintChanges
+  \clearpage \PrintIndex
+%    \end{macrocode}
+%    When this file is read directly by \LaTeX\ without the intervention
+%    of \DS, the following line will make \TeX\ stop
+%    reading.
+%    \begin{macrocode}
+\end{document}
+%    \end{macrocode}
+%    End of driver module.
+%    \begin{macrocode}
+%</driver>
+%    \end{macrocode}
+%    \noindent\null\par
+%
+% \section{The code for the \protect\packlass{\letteracdp} class}
+%
+%    This part of the file goes into \filedir{\letteracdp.cls}.
+%    \begin{macrocode}
+%<*letter>
+%    \end{macrocode}
+%    The reader must be warned that this is only a preliminary release
+%    of this code: a thorough reorganization of the macros has already
+%    been planned for future releases.  Instead of putting all the code
+%    in a single file and giving it the form of a document class,
+%    in future releases the code will be split into several files,
+%    part of which will be packages, part definition and/or
+%    configuation files, and so on.
+%
+%    \subsection{Identification}
+%
+%    I don't remember exactly why I asked for the June 1997 release
+%    of \LaTeXe, but I am sure that there was a reason; so, let us
+%    continue to ask for it.
+%    \begin{macrocode}
+\NeedsTeXFormat{LaTeX2e}[1997/06/01] % LaTeX2e is required!
+%    \end{macrocode}
+%    The usual identification; the string \texttt{(**incomplete**)}
+%    will eventually be removed, I hope!
+%    \begin{macrocode}
+\ProvidesClass{letteracdp}
+              [2018/02/08 v0.36d (**incomplete**)]
+%    \end{macrocode}
+%    Print a copyright message on the terminal, just below the name
+%    of the class.
+%    \begin{macrocode}
+\typeout{Copyright (C) 1999-2018 by Gustavo MEZZETTI,
+  all rights reserved.}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@letteracdp}
+%    Define a macro containing the name of the class; it will be used
+%    in error and warning messages.  This is done for two reasons:
+%    first of all, to save tokens in macro definitions, but also to
+%    avoid the risk of mispelling the name of the class in some place.
+%    \begin{macrocode}
+\@ifdefinable\@letteracdp{\def\@letteracdp{letteracdp}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \subsection{Initial code}
+%
+%    \begin{macro}{\Coordinamento}
+%    \changes{0.36d}{2018 Feb 08}{Made the accent of ``Universit\`a'' 
+%      independent of the currently selected font encoding.}^^A
+%    Define the following macros near the beginning of the code, so it
+%    will be easy to change them.  The first one is the full name of the
+%    \emph{Coordinamento}:
+%    \begin{macrocode}
+\newcommand*\Coordinamento{%
+  Coordinamento dei Dottorandi e dei Dottori di Ricerca
+  dell'Universit\`a di Padova%
+}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\CoordinamentoWWW}
+%    The second one is its web address:
+%    \begin{macrocode}
+\newcommand*\CoordinamentoWWW{%
+  http://www.dei.unipd.it/\string~assdott/%
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Declare the fonts used to print the letterhead and the footer.  In 1999
+%    I~knew so little about font selection in \LaTeXe\ that I~believed that it
+%    was necessary to declare them as ``fixed fonts'' in order to preserve them
+%    from being affected by options (\emph{e.g.}, \opz{12pt}), packages
+%    (\emph{e.g.}, \opz{times}), and so on.  Of course, this is nonsense, and it
+%    is probably wiser to switch to "\usefont"; but for the moment (vers.~0.36d)
+%    I~am not (yet) going to do so.
+%    \changes{0.36d}{2018 Feb 08}{Switched the fonts for the CDP\ letterhead 
+%      back to OT1 encoding.}^^A
+%    Note that, in vers.~0.36d, the fonts for the CDP\ letterhead have been
+%    switched back to OT1 encoding.
+%    \begin{macro}{\@lh@nss}
+%    Main font for letterhead is Computer Modern Sans Serif 12pt
+%    (LetterHead\slash Normal Sans Serif):
+%    \begin{macrocode}
+\DeclareFixedFont\@lh@nss{OT1}{cmss}{m}{n} {12}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@lh@bss}
+%    A couple of initials are printed using a bigger font, that is,
+%    Computer Modern Sans Serif 17pt (LetterHead\slash Bigger Sans
+%    Serif):
+%    \begin{macrocode}
+\DeclareFixedFont\@lh@bss{OT1}{cmss}{m}{n} {17}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@lh@rm}
+%    Main font for footer: Computer Modern Roman 9pt
+%    (LetterHead\slash RoMan):
+%    \begin{macrocode}
+\DeclareFixedFont\@lh@rm {OT1}{cmr} {m}{n} {9}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@lh@it}
+%    The words ``World Wide Web'' are printed in italics
+%    (LetterHead\slash ITalics):
+%    \begin{macrocode}
+\DeclareFixedFont\@lh@it {OT1}{cmr} {m}{it}{9}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@lh@tt}
+%    And finally, the web address is printed in teletype font
+%    (LetterHead\slash TeleType):
+%    \begin{macrocode}
+\DeclareFixedFont\@lh@tt {OT1}{cmtt}{m}{n} {9}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@ptsize}
+%    The following macro will be used later to decide which ``class
+%    layout'' file to load.
+%    \begin{macrocode}
+\newcommand\@ptsize{}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    A couple of useful commands that are missing from the \LaTeX\
+%    kernel; we leave this explicative comment in the code too.
+%    \begin{macrocode}
+%% A couple of useful things that are missing from the LaTeX kernel:
+%    \end{macrocode}
+%    \begin{macro}{\@newrigidlength}
+%    The first is similar to "\newlength", but allocates a
+%    \textoken{dimen} rather than a \textoken{glue}.
+%    \begin{macrocode}
+\@ifdefinable\@newrigidlength{\def\@newrigidlength#1{%
+  \@ifdefinable#1{\newdimen#1}%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@msetlength}
+%    The second can be used to say, for instance,
+%\begin{verbatim}
+%\@msetlength{\someRubberLength}{2}{\anotherRubberLength}
+%\end{verbatim}
+%    to set "\someRubberLength" to twice the value of
+%    "\anotherRubberLength", without destroying the stretch and
+%    shrink components (recall that, on the contrary,
+%\begin{verbatim}
+%\setlength{\someRubberLength}{2\anotherRubberLength}
+%\end{verbatim}
+%    only sets the \emph{natural length} of "\someRubberLength" to
+%    twice the \emph{natural length} of "\anotherRubberLength", and
+%    both the stretch and shrink components of "\someRubberLength" to
+%    zero).
+%    \begin{macrocode}
+\@ifdefinable\@msetlength{\def\@msetlength#1#2#3{%
+  #1#3\multiply#1#2\relax
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    A number of counter, lengths, etc.\ are defined here, early in the code, to
+%    detect as soon as possible if any name conflicts with an already defined
+%    one.  The idea was that, since the class is pretty long, it is better to
+%    avoid to discover near the end that it cannot be used because of a name
+%    that is already defined; but of course, with the speed of modern computers
+%    this is not at all a problem, so this is just more nonsense that should be
+%    eliminated.  Presently, however, they are almost all listed here; for many
+%    of them, some explanations are given here, and a more precise description
+%    is deferred until the spot where the corresponding entity is used.
+%
+%    \counterindex{letter}
+%    First, we introduce a counter to keep track of the number of letters
+%    produced.  \textbf{Warning:} {\em this counter is used also for
+%    internal bookkeeping, so don't change its value unless you know what
+%    you are doing!}
+%    \begin{macrocode}
+\newcounter{letter}
+%    \end{macrocode}
+%
+%    \counterindex{emptyaddrlabels}
+%    The following five counters are used in connection with the
+%    address labels optionally printed at the end of a compiled file.
+%    The \cnt{emptyaddrlabels} counter holds the number of labels to
+%    leave blank when starting to print (the first sheet of) the address
+%    labels; this is useful if some labels on the same sheet have already
+%    been peeled off.
+%    \begin{macrocode}
+\newcounter{emptyaddrlabels}
+%    \end{macrocode}
+%    \counterindex{addrlabelrows}
+%    A single sheet of address labels contains many labels.  For example,
+%    in the well-known (in the U.S.) Avery 5352 format each sheet
+%    contains ten labels, organized in two columns and five rows.  Other
+%    formats contain different number of rows and columns of labels.  To
+%    cope with all these different formats, the number of rows and
+%    columns of labels is kept in two counters: \cnt{addrlabelrows} holds
+%    the number of rows
+%    \begin{macrocode}
+\newcounter{addrlabelrows}
+%    \end{macrocode}
+%    \counterindex{addrlabelcolumns}
+%    and \cnt{addrlabelcolumns} holds the number of columns.
+%    \begin{macrocode}
+\newcounter{addrlabelcolumns}
+%    \end{macrocode}
+%    \counterindex{label}
+%    The \cnt{addrlabelrows} and \cnt{addrlabelcolumns} counters are
+%    usually set once for all by the code provided in a suitable
+%    "\DeclareOption" declaration, as the result of the user's request of
+%    one of the options devoted to specifying the address label format
+%    (\opz{105x37labels}, etc.).  In some exceptional circumstances, they
+%    can also be reset by the user, but even in this case, once set they
+%    are not changed any more.  They are therefore not real ``counters'',
+%    but rather (style) parameters.  The following two counters, instead,
+%    are ``real'', \emph{running} counters: they hold a running index
+%    which identifies the current label.  The \cnt{label} counter holds
+%    the index of a label inside a given letter
+%    \begin{macrocode}
+\newcounter{label}[letter]
+%    \end{macrocode}
+%    \counterindex{totallabel}
+%    while the \cnt{totallabel} counter holds the global index of a
+%    label, that is, the index of the label in the whole document.
+%    \begin{macrocode}
+\newcounter{totallabel}
+%    \end{macrocode}
+%    It is possible that a single letter has more than one label
+%    associated, because sometimes letters are sent to more than one
+%    addressee.
+%
+%    \counterindex{equation}
+%    \counterindex{footnote}
+%    \counterindex{mpfootnote}
+%    In our document class, the letter is the main unit in which the
+%    document is organized.  Therefore, we want that equations, footnotes,
+%    and footnotes inside minipages be numbered within letters.
+%    \begin{macrocode}
+\@addtoreset{equation}{letter}
+\@addtoreset{footnote}{letter}
+\@addtoreset{mpfootnote}{letter}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@lh@left@margin}
+%    The second type of parameters we are going to define are rigid lengths
+%    (\textoken{dimen}'s).  The first two govern the position of the CDP\ seal
+%    with respect to the text margins (see also fig.~\ref{fig:plo} on
+%    page~\pageref{fig:plo}).  More precisely, "\@lh@left@margin" is the
+%    horizontal distance from the left margin of text to the \emph{right} edge
+%    of the seal\ldots
+%    \begin{macrocode}
+\@newrigidlength\@lh@left@margin
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@lh@right@margin}
+%    \ldots and "\@lh@right@margin" is the distance from the right edge of
+%    the rule found in the rightmost part of the letterhead to the right
+%    margin of text.
+%    \begin{macrocode}
+\@newrigidlength\@lh@right@margin
+%    \end{macrocode}
+%    \end{macro}
+%    A couple of lenghts used as internal registers, to hold
+%    values that must be passed to certain macros---we shall explain
+%    their use when we come to it.
+%    \begin{macrocode}
+\@newrigidlength\@block@inden
+\@newrigidlength\@block@width
+%    \end{macrocode}
+%    \begin{macro}{\longindentation}
+%    The following are style parameters used to govern the typesetting
+%    of the addresses and of the signature.  Some of them, in turn, are
+%    defined in terms of another, crucial style parameter, the so-called
+%    ``long indentation''; this is the length by which items that appear
+%    in the right-hand half of the letter should be indented: roughly, it
+%    is equal to half the value of "\textsize", but it can be fine-tuned
+%    at ``"\begin{document}"-time'' for better alignment with some parts
+%    of the letterhead.
+%    \begin{macrocode}
+\@newrigidlength\longindentation
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\senderindentation}
+%    The amount by which the sender address should be indented:
+%    \begin{macrocode}
+\@newrigidlength\senderindentation
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\senderwidth}
+%    The width of the column in which the sender address should be
+%    typeset:
+%    \begin{macrocode}
+\@newrigidlength\senderwidth
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addresseeindentation}
+%    The indentation\ldots
+%    \begin{macrocode}
+\@newrigidlength\addresseeindentation
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addresseewidth}
+%    \ldots and column width for the addresse address:
+%    \begin{macrocode}
+\@newrigidlength\addresseewidth
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\signatureindentation}
+%    Indentation\ldots
+%    \begin{macrocode}
+\@newrigidlength\signatureindentation
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\signaturewidth}
+%    \ldots and width for the signature:
+%    \begin{macrocode}
+\@newrigidlength\signaturewidth
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\signaturerulewidth}
+%    The width of the rule drawn by the ``factory'' definition of
+%    "\signaturerule" (which is backed up in "\CDPFactorySignatureRule"):
+%    \begin{macrocode}
+\@newrigidlength\signaturerulewidth
+  \setlength\signaturerulewidth{5cm}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\foldedheight}
+%    There are macros that provide the ability to typeset letters that
+%    are going to be folded before being put into the envelopes; these
+%    macros ensure that no text is typeset astride of the folding.  The
+%    vertical distance from the upper edge of the \emph{paper} (not of
+%    the text) to the folding is kept in "\foldedheight".  A value of
+%    zero or less (\emph{e.g.}, $-"\maxdimen"$) prohibits folded letters:
+%    this can be useful for certain paper sizes, and for safety it is set
+%    here as the default.  For paper sizes that allow folded letters, the
+%    actual value of "\foldedheight" is set by the code given in the
+%    relevant "\DeclareOption".
+%    \begin{macrocode}
+\@newrigidlength\foldedheight
+  \setlength\foldedheight{-\maxdimen}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@folding@ht}
+%    In general, the default setting of "\foldedheight" provided by the
+%    option handling mechanism should be sufficient.  However, the user
+%    is allowed to change the value of "\foldedheight", preferably in the
+%    preamble, but also in the document body, if a certain simple
+%    precaution is taken.  This can be useful if one wants to alter the
+%    default behavior, \emph{e.g.}, to have letters that are two-folded
+%    rather then three-folded, or to allow folded letters also when using
+%    a paper format, like A5, that normally does not allow them.  Useful,
+%    sure, but it rises a problem: the algorithm that decides where to
+%    split the text between the part that must go above the folding and
+%    the part that must go below it requires that the value of
+%    "\foldedheight" lie within a certain range.  Obviously we cannot ask
+%    the user to know what range is acceptable, so we adopt the following
+%    solution: we define an ``internal backup'' of "\foldedheight",
+%    called "\@folding@ht" for historical reasons; then, the user is
+%    asked to call the macro "\checkfoldedheight" (see below) whenever
+%    (s)he changes the value of "\foldedheight"; this macro checks the
+%    new value and, if it is OK, copies it in the internal dimension
+%    "\@folding@ht" (actually, after some scaling conversions), otherwise
+%    it sets an internal flag which disables folded letters and issues a
+%    warning.  A slight variant of "\checkfoldedheight", which differs
+%    only in the warning produced, is called automatically at the
+%    "\begin{document}", so the user is \emph{not} required to call
+%    "\checkfoldedheight" if the changes to "\foldedheight" are made in
+%    the preamble.
+%    \begin{macrocode}
+\@newrigidlength\@folding@ht
+%    \end{macrocode}
+%    \end{macro}
+%    The following three dimensions will be described when we come to
+%    the point where they are used.
+%    \begin{macrocode}
+\@newrigidlength\@lh@folding@ht
+\@newrigidlength\@above@folding@margin
+\@newrigidlength\@above@folding@shrink
+%    \end{macrocode}
+%
+%    Now we pass to rubber lengths, \emph{i.e.}, \TeX's
+%    \textoken{skip}'s.  The first two are something like internal
+%    registers used to pass certain style parameters back and forth
+%    between macros.
+%    \begin{macrocode}
+\newlength\@block@space
+\newlength\@block@andspace
+%    \end{macrocode}
+%    \begin{macro}{\@below@folding@skip}
+%    This is an internal style parameter which specifies the amount of
+%    vertical blank space that should be left, in folded letters, between
+%    the folding and the text that follows it.  It can be redefined in
+%    packages or other classes, or, in an emergency, by the final user.
+%    It is a rubber length, but in this class it is assigned, as we shall
+%    see later, a value without stretch or shrink components.  Note that
+%    the actual space left between the folding and the text will usually
+%    be greater than, or at most equal to, the value of
+%    "\@below@folding@skip", because lines of text are usually aligned to
+%    integer multiples of half the "\baselineskip".
+%    \begin{macrocode}
+\newlength\@below@folding@skip
+%    \end{macrocode}
+%    \end{macro}
+%
+%    The following ten (rubber) length are style parameters that affect
+%    the amount of vertical space left before and after certain building
+%    blocks, like addresses and signature.  The user can freely change
+%    them with "\setlength".  Note that all these spaces are added with
+%    "\addvspace", so only the largest one survives if two of them occur
+%    in a row.
+%    \begin{macro}{\aboveaddressvspace}
+%    The amount of vertical space above the sender's or addressee's
+%    address:
+%    \begin{macrocode}
+\newlength\aboveaddressvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\andaddressvspace}
+%    The amount of vertical space between two consecutive addresses
+%    separated with "\and" or "\andcc":
+%    \begin{macrocode}
+\newlength\andaddressvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\belowaddressvspace}
+%    The amount of vertical space below the sender's or addressee's
+%    address:
+%    \begin{macrocode}
+\newlength\belowaddressvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\abovesubjectvspace}
+%    The amount of vertical space above the subject:
+%    \begin{macrocode}
+\newlength\abovesubjectvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\presubjectvspace}
+%    The amount of vertical space between the text specified with
+%    "\presubject" (if any) and the main body of the subject:
+%    \begin{macrocode}
+\newlength\presubjectvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\belowsubjectvspace}
+%    The amount of vertical space below the subject:
+%    \begin{macrocode}
+\newlength\belowsubjectvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\abovesignaturevspace}
+%    The amount of vertical space above the signature:
+%    \begin{macrocode}
+\newlength\abovesignaturevspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\abovesignatureshortvspace}
+%    The amount of vertical space above the signature when the
+%    \mbox{$*$-form} of the "\makesignature" command is used (this
+%    happens, for instance, when the \mbox{$*$-form} of the
+%    "\closing" command is used):
+%    \begin{macrocode}
+\newlength\abovesignatureshortvspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\belowsignaturevspace}
+%    The amount of vertical space below the signature:
+%    \begin{macrocode}
+\newlength\belowsignaturevspace
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\belowpresentationvspace}
+%    The amount of vertical space below the presentation as a whole
+%    (the presentation contains the sender address, the addressee
+%    address, and the optional subject); this also ends the block of
+%    these style parameters:
+%    \begin{macrocode}
+\newlength\belowpresentationvspace
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Allocation of some other rigid lengths (\textoken{dimen}'s)
+%    follows: these concern the layout of the sheets of address
+%    labels that the user wants to employ.  To save a few keystrokes,
+%    we define the "\do" macro to do the allocation and to initialize
+%    the value of the allocated length to zero.
+%    \begin{macrocode}
+\def\do#1{\@newrigidlength #1\setlength #1\z@}
+%    \end{macrocode}
+%    Then we allocate and initialize the individual lengths.
+%    \begin{macro}{\addrlabelsleftmargin}
+%    This is the amount of horizontal space between the left edge of the
+%    sheet of address labels and the left edge of the leftmost column of
+%    labels on the sheet.
+%    \begin{macrocode}
+\do\addrlabelsleftmargin
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabelstopmargin}
+%    This is the amount of vertical space between the top edge of the
+%    sheet of address labels and the top edge of the upper row of labels
+%    on the sheet.
+%    \begin{macrocode}
+\do\addrlabelstopmargin
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabelshsep}
+%    This is the amount of horizontal space between two columns of labels
+%    on the sheet.
+%    \begin{macrocode}
+\do\addrlabelshsep
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabelsvsep}
+%    This is the amount of vertical space between two rows of labels on
+%    the sheet.
+%    \begin{macrocode}
+\do\addrlabelsvsep
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabelborder}
+%    Normally, you don't want to write into the labels starting from
+%    their physical border: you want to leave a little margin between the
+%    text inside the labels and their edges.  The amount of margin is
+%    kept in this style parameter (sorry, no provision is made to specify
+%    different margins in the two directions).
+%    \begin{macrocode}
+\do\addrlabelborder
+%    \end{macrocode}
+%    \end{macro}
+%
+%    The following four lengths don't have reasonable default values,
+%    so they are not initialized here.  The code for each individual
+%    address label option will initialize the first two, and the
+%    other two are computed later.
+%    \begin{macro}{\addrlabelwidth}
+%    The (horizontal) width of a single address label.
+%    \begin{macrocode}
+\@newrigidlength\addrlabelwidth
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabelheight}
+%    The (vertical) height of a single address label.
+%    \begin{macrocode}
+\@newrigidlength\addrlabelheight
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabeltrimwidth}
+%    This is a computed value, that the user should regard as
+%    read-only: it is the width of a single address label
+%    ("\addrlabelwidth"), diminished by twice the width of the
+%    border ("\addrlabelborder").
+%    \begin{macrocode}
+\@newrigidlength\addrlabeltrimwidth
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\addrlabeltrimheight}
+%    Analogous: "\addrlabelheight" diminished by twice
+%    "\addrlabelborder".  This ends this block of code.
+%    \begin{macrocode}
+\@newrigidlength\addrlabeltrimheight
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Now, we just declare a few names we are going to use.  The idea
+%    is to trigger an error message if one of them is already defined.
+%    \begin{macro}{\@cdp@reserved}
+%    This is a reserved name that will be used as a
+%    ``general-purpose'' container, much like "\reserved@a", etc.
+%    \begin{macrocode}
+\@ifdefinable\@cdp@reserved{}
+%    \end{macrocode}
+%    \end{macro}
+%    Miscellaneous names, we shall describe them in a more
+%    appropriate place.
+%    \begin{macrocode}
+\@ifdefinable\@empty@block{}
+\@ifdefinable\@beginlabels{}
+\@ifdefinable\@beginlabelgroup{}
+\@ifdefinable\@mlabel{}
+\@ifdefinable\@endlabelgroup{}
+\@ifdefinable\@endlabels{}
+\@ifdefinable\startaddrlabel{}
+\@ifdefinable\stopaddrlabel{}
+\@ifdefinable\ifactuallabel{}
+\@ifdefinable\ChosenMakeOpening{}
+\@ifdefinable\ChosenMakeClosing{}
+\@ifdefinable\ChosenMakeSignature{}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@lett@decl}
+%    We define a token register used to save declarations to execute
+%    when a letter begins (see below).
+%    \begin{macrocode}
+\@ifdefinable\@lett@decl{\newtoks\@lett@decl}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    We finally arrive to something simple and clearly comprehensible.
+%    We initialize the addresses, the signature, etc.  to empty strings.
+%    To do that, we define the "\do" macro as follows:
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\let#1\@empty}}
+%    \end{macrocode}
+%    \begin{macro}{\thesenderaddress}
+%    The address of the sender, \emph{including her/his name}:
+%    \begin{macrocode}
+\do\thesenderaddress
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thesendername}
+%    The name of the sender (essentially, this is provided only for
+%    compatibility with the \packlass{letter} standard \LaTeX\ class):
+%    \begin{macrocode}
+\do\thesendername
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thesendersignature}
+%    The signature of the sender:
+%    \begin{macrocode}
+\do\thesendersignature
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thesenderlocation}
+%    The room number, etc., of the sender:
+%    \begin{macrocode}
+\do\thesenderlocation
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thesenderphone}
+%    The phone number of the sender:
+%    \begin{macrocode}
+\do\thesenderphone
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\theaddresseeaddress}
+%    The complete address of the addressee, \emph{including her/his
+%    name, title, etc.}:
+%    \begin{macrocode}
+\do\theaddresseeaddress
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\theaddresseename}
+%    The name of the addressee (used in page headings):
+%    \begin{macrocode}
+\do\theaddresseename
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thesubject}
+%    The subject of the letter:
+%    \begin{macrocode}
+\do\thesubject
+%    \end{macrocode}
+%    \end{macro}
+%
+%    There are also some internal macros that need to be initialized to
+%    "\@empty".
+%    \begin{macro}{\@subject@style}
+%    The subject can be typeset either in medium weight or in
+%    boldface.  This is achieved by inserting the "\@subject@style"
+%    token in front of it: its default definition given here makes
+%    this token a no-op (no font attributes are changed), but the code
+%    that implements options like \opz{mediumsubject} or
+%    \opz{boldsubject} can "\let" this token be equal to, say,
+%    "\mdseries" or "\bfseries", to obtain the desired changes in the
+%    font attributes.  If more than one attribute needed to be
+%    changed (\emph{e.g.}, if somebody wanted to define a
+%    \opz{bolditalicsubject} option), then "\def" should be used
+%    instead of "\let"; for instance, one would write
+%    \begin{verbatim}\def\@subject@style{\bfseries\itshape}\end{verbatim}
+%    We don't make "\@subject@style" a token register because the
+%    ``"\let" case'' is the most common.
+%    \begin{macrocode}
+\do\@subject@style
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@signature@style}
+%    This is analogous to "\@subject@style", but for the signature.
+%    The code for the \opz{uprightsignature} option "\let"s it equal to
+%    "\upshape", and the code for the \opz{italicsignature} option to
+%    "\itshape".
+%    \begin{macrocode}
+\do\@signature@style
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@place}
+%    The place where the letter is written: starting from version~0.34,
+%    this macro is used as the default value for the optional argument of
+%    "\@makeopening", "\makedate", etc.  It is logically and functionally
+%    analogous to "\@date".
+%    \begin{macrocode}
+\do\@place
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@cdp@begin@letter@hook}
+%    \changes{0.36d}{2018 Feb 08}{Name has been changed (it used to be
+%      \texttt{\protect\bslash @begin@letter@hook}) to avoid clash with
+%      a macro built by the \protect\packlass{etoolbox} package.}^^A
+%    This hook is executed when a letter starts, at the very end of the setup of
+%    the ``letter-making'' environment, just after the declarations stored in
+%    "\@lett@decl".  It may prove useful in packages and derived classes, and in
+%    fact it is used by the \packlass{articoletteracdp} class.  It is not a
+%    token register because it is envisioned that many independent segments of
+%    code will want to store tokens in it, and this can easily be achieved with
+%    the "\g@addto@macro" function, which requires that its argument be a macro,
+%    not a token register.  In vers.~0.36d, the names of this hook and of the
+%    following one were changed to avoid a conflict with the \packlass{etoolbox}
+%    package..
+%    \begin{macrocode}
+\do\@cdp@begin@letter@hook
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@cdp@end@letter@hook}
+%    \changes{0.36d}{2018 Feb 08}{Same as
+%      \texttt{\protect\bslash @cdp@begin@letter@hook}.}^^A
+%    This is analogous to "\@cdp@begin@letter@hook", but is executed at the
+%    end of every ``letter-making'' environment, after its last page has
+%    been finished off and ejected, but before writing to the
+%    \filedir{.aux} file the information for the associated address labels.
+%    Note that there is another hook, called "\stopletter" and described
+%    later, which is executed \emph{before} ejecting the last page of
+%    the letter.
+%    \begin{macrocode}
+\do\@cdp@end@letter@hook
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@begin@block@or@and@hook}
+%    Vers.~0.36: new hook used in "\@block@everypar" to support signature
+%    rules.
+%    \begin{macrocode}
+\do\@begin@block@or@and@hook
+%    \end{macrocode}
+%    \end{macro}
+%
+%    The following macros are defined only inside a \env{subject}
+%    environment.  We want that they cause an error if used outside of that
+%    environment, but we also want to be sure that their names are not
+%    already defined.  We achieve this by calling "\@ifdefinable", and
+%    then "\let"ting the relevant token be "\@undefined".
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\let#1\@undefined}}
+\do\presubject
+\do\registered
+\do\registeredRR
+%    \end{macrocode}
+%
+%    The following are integer (numeric) style parameters: they are
+%    initialized later, and contain several penalty values used to assist
+%    \TeX\ in choosing sightful and meaningful page breaks, and also for
+%    other purposes that will be explained later.  For now we content
+%    ourselves with the simple allocation with "\newcount".
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\newcount#1}}
+%    \end{macrocode}
+%    The first five parameters are actually ``constants'' analogous to
+%    "\@lowpenalty", "\@medpenalty", and "\@highpenalty"; they are
+%    typically assigned very high penalty values, and their names all
+%    begin with "\@fold@" because they are used in connection with the
+%    algorithm that takes care of ``folded presentations'' (explained
+%    later).
+%    \begin{macrocode}
+\do\@fold@basepenalty
+\do\@fold@lowpenalty
+\do\@fold@medpenalty
+\do\@fold@highpenalty
+\do\@fold@toppenalty
+%    \end{macrocode}
+%    The real style parameters begin here.  Their values are assigned
+%    later, in various spots of the code; indeed, the values assigned
+%    vary according to certain circumstances, for example, they are
+%    changed from the default when a ``presentation'' is entered.
+%    We'll discuss all this later on.
+%    \begin{macro}{\@b@frompenalty}
+%    This is the penalty inserted at the beginning of a \env{sender}
+%    environment---the environment used to typeset the sender address.
+%    \begin{macrocode}
+\do\@b@frompenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@i@frompenalty}
+%    This is the penalty inserted before additional sender addresses
+%    separated with "\and".
+%    \begin{macrocode}
+\do\@i@frompenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@e@frompenalty}
+%    This is the penalty inserted at the end of a \env{sender}
+%    environment.
+%    \begin{macrocode}
+\do\@e@frompenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@b@topenalty}
+%    This is the penalty inserted at the beginning of an
+%    \env{addressee} environment---the environment used to typeset the
+%    addressee address.
+%    \begin{macrocode}
+\do\@b@topenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@i@topenalty}
+%    This is the penalty inserted before additional addressee addresses
+%    separated with "\and" or "\andcc".
+%    \begin{macrocode}
+\do\@i@topenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@e@topenalty}
+%    This is the penalty inserted at the end of an \env{addressee}
+%    environment.
+%    \begin{macrocode}
+\do\@e@topenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@b@subjpenalty}
+%    This is the penalty inserted at the beginning of a \env{subject}
+%    environment---the environment used to typeset the subject.
+%    \begin{macrocode}
+\do\@b@subjpenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@e@subjpenalty}
+%    This is the penalty inserted at the end of a \env{subject}
+%    environment.
+%    \begin{macrocode}
+\do\@e@subjpenalty
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@e@prespenalty}
+%    This is the penalty inserted at the end of a presentation as a
+%    whole.
+%    \begin{macrocode}
+\do\@e@prespenalty
+%    \end{macrocode}
+%    \end{macro}
+%    The following are two internal registers, used to pass penalty
+%    values back and forth between macros.
+%    \begin{macrocode}
+\do\@i@penalty
+\do\@e@penalty
+%    \end{macrocode}
+%    \begin{macro}{\@cdp@gencount}
+%    We also take the opportunity to define a general-purpose numeric
+%    register, used for short-term storage when needed.  This ends the
+%    block of count registers.
+%    \begin{macrocode}
+\do\@cdp@gencount
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Six internal switches are defined next.
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\newif#1}}
+%    \end{macrocode}
+%    \begin{macro}{\if@use@eepic@}
+%    The user can request, through the \opz{usePS} option, that the
+%    \packlass{eepic} package be used to trace the lines that make up the CDP\ 
+%    seal, for better graphical result; the user's indication, however, will be
+%    honored only if the \packlass{eepic} package is available on the system (of
+%    course!).  This switch is set to ``true'' if the \packlass{eepic} package
+%    is present and should be used.
+%    \begin{macrocode}
+\do\if@use@eepic@
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\if@do@fold@}
+%    This switch is ``true'' when folded letters are allowed, and
+%    ``false'' when they are shunned; the setting is made by the
+%    "\checkfoldedheight" command, and also at
+%    ``"\begin{document}"-time''.
+%    \begin{macrocode}
+\do\if@do@fold@
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\if@making@labels@}
+%    Prior to version~0.36, the code for generating the address labels (that
+%    had been copied from the standard \packlass{letter} class) wrote to the
+%    \filedir{.aux} file the data concerning the addresses even when no labels
+%    were being produced.  This is totally useless.  Starting from
+%    version~0.36, the following conditional has been introduced in order to
+%    avoid this.
+%    \begin{macrocode}
+\do\if@making@labels@
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\if@signature@rule@}
+%    True if a typeset signature should be surmounted by a ``signature rule''
+%    intended to guide the signer's hand.  New in vers.~0.36 (2015 Feb~08).
+%    \begin{macrocode}
+\do\if@signature@rule@
+%    \end{macrocode}
+%    \end{macro}
+%    The other two switches cannot be explained here.  They are defined
+%    differently, without using "\newif", so that they are always changed
+%    "\global"ly.
+%    \begin{macrocode}
+\@ifdefinable\if@new@block@{
+  \def\@new@block@true {\global\let\if@new@block@\iftrue }
+  \def\@new@block@false{\global\let\if@new@block@\iffalse}
+}
+\@ifdefinable\if@empty@and@{
+  \def\@empty@and@true {\global\let\if@empty@and@\iftrue }
+  \def\@empty@and@false{\global\let\if@empty@and@\iffalse}
+}
+%    \end{macrocode}
+%
+%    We need the following box registers to hold precompiled parts of
+%    the letterhead and of the footer.
+%    \begin{macro}{\@logo@box@base}
+%    This holds the main part of the CDP\ seal; more precisely, that part that
+%    appears both in the \ldots\sty{letterhead} and in the \sty{logo}\ldots page
+%    styles.
+%    \begin{macrocode}
+\newsavebox\@logo@box@base
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@logo@box@addS}
+%    This holds the part of the CDP\ seal that should be added to the part
+%    contained in "\@logo@box@base" to obtain the seal as it appears in the
+%    \sty{logo}\ldots page styles.
+%    \begin{macrocode}
+\newsavebox\@logo@box@addS
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@logo@box@addL}
+%    This holds the part of the CDP\ seal that should be added to the part
+%    contained in "\@logo@box@base" to obtain the seal embedded in the
+%    \ldots\sty{letterhead} page styles.
+%    \begin{macrocode}
+\newsavebox\@logo@box@addL
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@oordinamento@box}
+%    This holds the writing ``oordinamento dei Dottorandi di Padova''
+%    that appears in the letterhead, with the initial~``C'' being
+%    supplied by the seal.
+%    \begin{macrocode}
+\newsavebox\@oordinamento@box
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@name@and@WWW@box}
+%    This holds the footer used in the \sty{firstletterhead} and
+%    \sty{foldedletterhead} page styles, which contains the full name of
+%    the \emph{Coordinamento} and its web address.  This ends the block
+%    of box registers, too.
+%    \begin{macrocode}
+\newsavebox\@name@and@WWW@box
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\and}
+%    It is possible to specify several addresses (both for the sender
+%    and the addressee) as well as several signatures; the various parts
+%    are separated by "\and" commands.  Strictly speaking, it is an error
+%    to expand the token "\and" anywhere but inside the \env{sender},
+%    \env{addressee}, and \env{signatureenv} environments (the
+%    environments used to produce the sender address, the addressee
+%    address, and the signature, repectively); hence, the correct thing
+%    to do here would be to initialize "\and" to produce an error
+%    message, and then redefine it in the various environments, as
+%    required in each case.  But alas, the code for \packlass{\letteracdp}
+%    is still incomplete, and this is one of the things I still have to
+%    finish: I don't know exactly how to handle a misplaced "\and", so,
+%    for now, I simply decide to ignore it.
+%    \begin{macrocode}
+\let\and\relax
+%    \end{macrocode}
+%    Of course, this definition will be changed inside the
+%    abovementioned environments, where "\and" must have a special
+%    meaning.
+%    \end{macro}
+%    \begin{macro}{\andcc}
+%    Only inside an \env{addressee} environment, the token "\andcc" may
+%    be used in place of "\and" to separate addresses of persons to which
+%    the letter is sent as a carbon copy.  Its default definition,
+%    however, is to act as "\and".
+%    \begin{macrocode}
+\@ifdefinable\andcc{\def\andcc{\and}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    We need to save the definitions, as initialized by the \LaTeX\
+%    kernel, of a couple of macros.
+%    \begin{macro}{\m@kel@bel}
+%    Saved definition of "\makelabel".
+%    \begin{macrocode}
+\@ifdefinable\m@kel@bel{\let\m@kel@bel\makelabel}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@@vspace}
+%    Saved definition of "\vspace".
+%    \begin{macrocode}
+\@ifdefinable\@@vspace{\let\@@vspace\vspace}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@indent@pref}
+%    This is a multi-way switch used to implement the \opz{indent},
+%    \opz{noindent}, etc.\ options, which govern the way in which
+%    paragraphs of letters (except~P.S.) are indented.  The code associated
+%    with the various options "\let"s this token equal to one of the
+%    following keys, which will be interpreted later as specified:
+%    \begin{description}
+%      \item[F (for ``fixed indent'').]
+%        Set "\parindent" to one tenth of "\textwidth", with a threshold
+%        value of 2~pica (that is, "\parindent" will be at least 2~pica, even
+%        if this is more than one tenth of "\textwidth").
+%      \item[N (for ``no ident'').]
+%        Set "\parindent" to 0~points.
+%      \item[L (for ``leave indent'').]
+%        The value of "\parindent" that was in effect outside of the
+%        current \ldots\env{letter}\ldots\ environment is retained.
+%      \item[O (sorry, I don't remember for what).]
+%        Set "\parindent" to the width of the last line of the salutation
+%        (\emph{i.e.}, the argument of "\opening" or "\makeopening"); if the
+%        salutation is not given, this is the same as~``F''.
+%
+%        2015 Feb~08 (v.~0.36): I~have conjectured that the choice of the
+%        letter~``O'' for this key could have been suggested by the initial of
+%        ``opening'', meaning, as it were, ``indent by the extent of the 
+%        opening''; but I~cannot remember of having thought of that.
+%    \end{description}
+%    The default setting is the same as the one implied by the
+%    \opz{indent} option.
+%    \begin{macrocode}
+\@ifdefinable\@indent@pref{\let\@indent@pref F}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\voidisOK}
+%    Sometimes, in a letter, you want to omit the sender or the
+%    addressee address, or the signature, and it is annoying to see a
+%    warning about an ``empty something'' that you left empty
+%    deliberately.  For this reason, inside the environments that produce
+%    the addresses and the signature you are allowed to use the command
+%    "\voidisOK" to disable such warnings.  The idea is that you say
+%    something like
+%\begin{verbatim}
+%\address{\voidisOK}
+%\end{verbatim}
+%    when you want to declare that the address has intentionally be
+%    left void; when the address is actually typeset (and this happens
+%    inside an \env{addressee} environment), the command "\voidisOK" will
+%    be expanded, causing the warning to be suppressed.  As for the
+%    command "\and", the right thing to do would be to define this
+%    command only inside the environments in which it can be used; but
+%    there are complications arising from the fact that the text
+%    specified inside an "\address" declaration can be expanded also at
+%    other times, for instance when typesetting the address labels.  For
+%    this reason, we take the shortcut of "\let"ting this command equal
+%    to "\@empty", so that it will be ignored when it occurs out of place.
+%    (We do not "\let" it equal to "\relax" because the latter could
+%    confuse an "\ignorespaces"; on the contrary, "\@empty" disappears
+%    upon "\write" and "\mark" operations, and this is quite OK\@.) Where
+%    appropriate, "\voidisOK" will be redefined to achieve the desired
+%    effect.
+%    \begin{macrocode}
+\@ifdefinable\voidisOK{\let\voidisOK\@empty}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\subjectnamegap}
+%    If present, the subject of a letter is typeset with hanging
+%    indentation, preceded by the text contained in the command
+%    "\subjectname" and separated from it by a certain amount of
+%    horizontal white space: the width of this white space is specified
+%    by the "\subjectnamegap" macro.  This is a macro and not a
+%    \textoken{dimen} register to allow the length to be specified in
+%    terms of the font-dependent units like ``em''.  Of course, the
+%    hanging indentation includes this horizontal space; note,
+%    however, that if "\subjectname" is empty than the
+%    "\subjectnamegap" space is not taken into account.
+%    \begin{macrocode}
+\newcommand*\subjectnamegap{.5em}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\closingindentation}
+%    As for the way of typesetting addresses, different countries have
+%    different uses about how to indent the closing of the letter: for
+%    instance, in Italy the closing is indented like any other, ordinary
+%    paragraph, whilst in anglo-saxon letters it is indented by the same
+%    amount by which the sender address is indented.  To cope with this,
+%    the "\closingindentation" command is introduced, to hold the amount
+%    of indentation for the closing: its default definition is
+%    "\parindent", so that the closing is indented like an ordinary
+%    paragraph, but a ``letter-making'' environment can redefine it,
+%    if necessary.  It is a command and not a length, because the
+%    value of "\parindent" can change, and actually does change, in
+%    the sequel.
+%    \begin{macrocode}
+\newcommand*\closingindentation{\parindent}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\signaturealignment}
+%    Different countries have different conventions also about how the
+%    signature should be aligned; for instance, in the U.S.  the
+%    signature is set ragged right, but with a hanging indentation equal
+%    to the hanging indentation of the sender address, which in the U.S.
+%    is printed on the right-hand half of the paper; in Italy, the
+%    signature is more or less centered between the margins, and if it
+%    contains more than one line, the lines are aligned at their
+%    midpoint.  In order to accomodate the various conventions, the token
+%    "\signaturealignment" is inserted at the beginning of the
+%    \env{signatureenv} environment (the environment one uses to typeset
+%    the signature); it is the responsability of the surrounding
+%    \ldots\env{letter}\ldots\ environment to "\let" this token equal to
+%    "\raggedright", "\centering", etc., as required by the particular
+%    letter being produced.  This makes it easy, for instance, to define
+%    an \env{asletter} (anglo-saxon letter) environment that prints
+%    letters that obey the U.S.  conventions.  The default setting given
+%    here has no special meaning: it just sets the signature ragged
+%    right.
+%    \begin{macrocode}
+\newcommand*\signaturealignment{\raggedright}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \subsection{Declaration of options}
+%
+%    As a general rule, options pertaining to the same functional group
+%    are declared in reverse order of desirability, the default option of
+%    the group being declared last.  This ensures that if more than
+%    one option of the same group is erroneously asked for by the
+%    user, the ``most desirable'' one (whatever this means) is
+%    executed last, thereby remaining in effect.
+%
+%    We begin with the options that support the usual page formats.
+%    For each such option, the associated code sets appropriate values
+%    for the "\paperheight" and "\paperwidth" parameters.  The code also
+%    sets the "\foldedheight" parameter, which, as explained above,
+%    contains the height at which the sheets of paper should be folded in
+%    order to put them into an envelope; this parameter is set to more or
+%    less one third of "\paperheight".  For some paper formats, folding
+%    is not adequate: for them, folded letters are disabled by setting
+%    "\foldedheight" to $-"\maxdimen"$.
+%    \begin{macrocode}
+\DeclareOption{executivepaper}
+   {\setlength\paperheight {10.5in}%
+    \setlength\paperwidth  {7.25in}%
+    \setlength\foldedheight{3.5in}}
+\DeclareOption{legalpaper}
+   {\setlength\paperheight {14in}%
+    \setlength\paperwidth  {8.5in}%
+    \setlength\foldedheight{4.7in}}
+\DeclareOption{letterpaper}
+   {\setlength\paperheight {11in}%
+    \setlength\paperwidth  {8.5in}%
+    \setlength\foldedheight{3.7in}}
+\DeclareOption{b5paper}
+   {\setlength\paperheight {250mm}%
+    \setlength\paperwidth  {176mm}%
+    \setlength\foldedheight{-\maxdimen}}
+\DeclareOption{a5paper}
+   {\setlength\paperheight {210mm}%
+    \setlength\paperwidth  {148mm}%
+    \setlength\foldedheight{-\maxdimen}}
+\DeclareOption{a4paper}
+   {\setlength\paperheight {297mm}%
+    \setlength\paperwidth  {210mm}%
+    \setlength\foldedheight{100mm}}
+%    \end{macrocode}
+%
+%    The \opz{landscape} option is implemented as usual, by
+%    exchanging the values of "\paperheight" and "\paperwidth" (note that
+%    this option is executed after any one of the options that sets the
+%    paper dimensions); but we also disable folded letters by setting
+%    "\foldedheight" to $-"\maxdimen"$, because usually one does not want
+%    to fold a letter set in landscape orientation!
+%    \begin{macrocode}
+\DeclareOption{landscape}
+   {\setlength\@tempdima   {\paperheight}%
+    \setlength\paperheight {\paperwidth}%
+    \setlength\paperwidth  {\@tempdima}%
+    \setlength\foldedheight{-\maxdimen}}
+%    \end{macrocode}
+%
+%    These are the usual options for setting the main font size: they are
+%    copied from the standard \LaTeX\ classes.  See, \emph{e.g.}, the
+%    documentation of the standard \packlass{letter} class for
+%    explanations.
+%    \begin{macrocode}
+\DeclareOption{12pt}{\renewcommand\@ptsize{2}}
+\DeclareOption{11pt}{\renewcommand\@ptsize{1}}
+\DeclareOption{10pt}{\renewcommand\@ptsize{0}}
+%    \end{macrocode}
+%
+%    The way of implementing the \opz{oneside}\slash\opz{twoside}
+%    options is again copied from the \packlass{letter} standard \LaTeX\
+%    class.
+%    \begin{macrocode}
+\if@compatibility
+  \DeclareOption{twoside}{%
+    \@latexerr{No `twoside' layout for letters}\@eha
+  }
+\else
+  \DeclareOption{twoside}{\@twosidetrue  \@mparswitchtrue}
+\fi
+\DeclareOption{oneside}{\@twosidefalse \@mparswitchfalse}
+%    \end{macrocode}
+%
+%    The \opz{onecolumn}\slash\opz{twocolumn} options are not
+%    declared in the \packlass{letter} standard \LaTeX\ class, but I prefer
+%    to declare them.  The \opz{twocolumn} options causes an error,
+%    because I have never seen letters typeset in two columns mode!
+%    \begin{macrocode}
+\DeclareOption{twocolumn}{%
+  \@latexerr{No `twocolumn' layout for letters}\@eha
+}
+%    \end{macrocode}
+%    The \opz{onecolumn} option is simply ignored, but it is
+%    declared, so that it is removed from the list of unused options.
+%    \begin{macrocode}
+\DeclareOption{onecolumn}{}
+%    \end{macrocode}
+%
+%    More options copied from the standard \LaTeX\ classes.
+%    \begin{macrocode}
+\DeclareOption{final}{\setlength\overfullrule{0pt}}
+\DeclareOption{draft}{\setlength\overfullrule{5pt}}
+\DeclareOption{leqno}{\input{leqno.clo}}
+\DeclareOption{fleqn}{\input{fleqn.clo}}
+%    \end{macrocode}
+%
+%    Now we have four options for setting the way in which the subject
+%    of a letter (if present) and the signature are printed.  As
+%    explained above, the setting is done by "\let"ting a conventional
+%    token equal to one of the usual NFSS commands used to set individual
+%    font attributes; if more than one attribute needed to be changed,
+%    "\def" would be used instead of "\let", but fortunately this is not
+%    necessary.
+%
+%    Options for the subject: it can be set in boldface type\ldots
+%    \begin{macrocode}
+\DeclareOption{boldsubject}{\let\@subject@style\bfseries}
+%    \end{macrocode}
+%    \ldots or in medium weight.
+%    \begin{macrocode}
+\DeclareOption{mediumsubject}{\let\@subject@style\mdseries}
+%    \end{macrocode}
+%
+%    Options for the signature: it can be set in italic shape\ldots
+%    \begin{macrocode}
+\DeclareOption{italicsignature}{\let\@signature@style\itshape}
+%    \end{macrocode}
+%    \ldots or in upright (normal) shape.
+%    \begin{macrocode}
+\DeclareOption{uprightsignature}{\let\@signature@style\upshape}
+%    \end{macrocode}
+%
+%    Vers.~0.36 (2015 Feb~08): new option \opz{signaturerule} requests that
+%    each typeset signature be surmounted by a ``signature rule'' intended to
+%    guide the signer's hand.  This, however, should not affect at all
+%    signatures contained in a \env{signatureenv*} environment, the variant of
+%    the \env{signatureenv} environment meant for situations in which the
+%    letter is not going to be signed by hand.
+%    \begin{macrocode}
+\DeclareOption{signaturerule}{\@signature@rule@true}
+%    \end{macrocode}
+%    The \opz{nosignaturerule} option (also new in vers.~0.36) is the opposite 
+%    of the above, and is the default.
+%    \begin{macrocode}
+\DeclareOption{nosignaturerule}{\@signature@rule@false}
+%    \end{macrocode}
+%    \emph{Remark:} the ability to draw a rule for handwritten signatures has
+%    been explicitly requested by some users of the \Bundle, but I~deem the use
+%    of such feature questionable, since only pupils in primary school need
+%    rules to guide their writing.  Nevertheless, this practice is admittedly
+%    ^^A ( paren match
+%    fairly common in the business world~:-), so it has now been supported.
+%
+%    Next, we have the options used to tell whether PostScript commands,
+%    inserted by means of the \packlass{eepic} package, should be used, or not,
+%    to draw the CDP\ seal.  Here we simply set the internal switch according to
+%    the user's request; if we later find that the \packlass{eepic} package is
+%    not available, we shall force the switch to false.
+%    \begin{macrocode}
+\DeclareOption{usePS}{\@use@eepic@true}
+\DeclareOption{noPS}{\@use@eepic@false}
+%    \end{macrocode}
+%    (These mean ``use PostScript'' and ``don't use PostScript'',
+%    respectively.)
+%
+%    Cheer up!  We are almost over!  (Just with the options, of
+%    course!)  We are now to the options for the paragraph
+%    indentation within letters.  They are implemented by setting an
+%    internal multi-value switch to a conventional key; the meaning of
+%    the keys has already been explained above.
+%    \begin{macrocode}
+\DeclareOption{smartindent}{\let\@indent@pref O}
+\DeclareOption{shortindent}{\let\@indent@pref L}
+\DeclareOption{noindent}{\let\@indent@pref N}
+\DeclareOption{indent}{\let\@indent@pref F}
+%    \end{macrocode}
+%
+%    The last three options deal with the format of the address
+%    labels.  As already said, the format is specified by
+%    initializing a number of \textoken{dimen} parameters which
+%    specify the ``geometry'' of the sheet of address labels.  Many
+%    of these parameters have a default value of 0~points: when this
+%    default is appropriate, the parameter is not re-initialized in
+%    the code given below.
+%
+%    We support the Avery 5352 address labels only for compatibility
+%    with the standard \packlass{letter} class.  I have never seen a sheet
+%    of these labels, and the code for the \opz{Avery5352labels}
+%    option simply assigns values to the parameters in a way that tries to
+%    imitate the geometry described by the code found in the
+%    \packlass{letter} class.
+%    \begin{macrocode}
+\DeclareOption{Avery5352labels}{%
+%    \end{macrocode}
+%    We have 5~rows of labels.
+%    \begin{macrocode}
+  \setcounter{addrlabelrows}{5}%
+%    \end{macrocode}
+%    Each row contains 2~labels, \emph{i.e.}, we have two columns of
+%    labels.
+%    \begin{macrocode}
+  \setcounter{addrlabelcolumns}{\tw@}%
+%    \end{macrocode}
+%    The left edge of the leftmost column is 35~points to the left of
+%    the \TeX\ origin, which in turn is 1~inch from the left edge of
+%    the paper.
+%    \begin{macrocode}
+  \setlength\addrlabelsleftmargin{-35\p@}%
+  \addtolength\addrlabelsleftmargin{1in}%
+%    \end{macrocode}
+%    The top edge of the topmost row is 50~points above
+%    the \TeX\ origin, which in turn is 1~inch from the top edge of
+%    the paper.
+%    \begin{macrocode}
+  \setlength\addrlabelstopmargin{-50\p@}%
+  \addtolength\addrlabelstopmargin{1in}%
+%    \end{macrocode}
+%    The two columns are separated by 26~points.
+%    \begin{macrocode}
+  \setlength\addrlabelshsep{26\p@}%
+%    \end{macrocode}
+%    Labels are 262~points wide by 2~inches high.
+%    \begin{macrocode}
+  \setlength\addrlabelwidth{262\p@}%
+  \setlength\addrlabelheight{2in}%
+}
+%    \end{macrocode}
+%
+%    The code for the labels I had the opportunity to actually see and
+%    measure is more elegant, and fits more naturally into the scheme.
+%    The following is the setting for the 70\,$\times$\,37 labels (the
+%    dimensions are given in~mm).
+%    \begin{macrocode}
+\DeclareOption{70x37labels}{%
+%    \end{macrocode}
+%    8~rows of labels.
+%    \begin{macrocode}
+  \setcounter{addrlabelrows}{8}%
+%    \end{macrocode}
+%    3~columns, \emph{i.e.}, 3~labels in each row.
+%    \begin{macrocode}
+  \setcounter{addrlabelcolumns}{\thr@@}%
+%    \end{macrocode}
+%    Labels are 70\,mm wide by 37\,mm high.
+%    \begin{macrocode}
+  \setlength\addrlabelwidth{70mm}%
+  \setlength\addrlabelheight{37mm}%
+%    \end{macrocode}
+%    We leave 6\,mm of margin between the border of the labels and the
+%    actual printing.
+%    \begin{macrocode}
+  \setlength\addrlabelborder{6mm}%
+}
+%    \end{macrocode}
+%    The setting for the 105\,$\times$\,37 labels (the default) is
+%    similar.
+%    \begin{macrocode}
+\DeclareOption{105x37labels}{%
+  \setcounter{addrlabelrows}{8}%
+  \setcounter{addrlabelcolumns}{\tw@}%
+  \setlength\addrlabelwidth{105mm}%
+  \setlength\addrlabelheight{37mm}%
+  \setlength\addrlabelborder{6mm}%
+}
+%    \end{macrocode}
+%
+%    \subsection{Option processing}
+%
+%    Nothing special to note here.
+%
+%    \emph{Begin to think (v.~0.34):} should I change the defaults as
+%    follows: \opz{boldsubject} in place of \opz{mediumsubject},
+%    \opz{italicsignature} in place of \opz{uprightsignature},
+%    \opz{shortindent} in place of \opz{indent}?
+%
+%    Ver.~0.36 (2015 Feb~08): not yet determined to change the default options.
+%    Added \opz{nosignaturerule}.
+%    \begin{macrocode}
+\ExecuteOptions{%
+  a4paper,10pt,oneside,onecolumn,final,%
+  mediumsubject,uprightsignature,nosignaturerule,noPS,indent,%
+  105x37labels%
+}
+\ProcessOptions\relax
+%    \end{macrocode}
+%
+%    \subsection{Package loading}
+%
+%    In this version of the \Bundle, all the original code is
+%    put in the file \filedir{\letteracdp.cls}, so in the normal operating
+%    mode no packages need to be loaded.  This will change in future
+%    releases: the code will be split among several packages, to allow
+%    the final user to request only some features and not the others;
+%    when this happens, this section will become much longer, in order to
+%    load all those packages.  However, even now it could be necessary to
+%    require the \packlass{eepic} package, if the user specified the
+%    \opz{usePS} option.  At this stage, the presence of this option can
+%    be tested for by means of the "\if@use@eepic@" switch.
+%    \begin{macrocode}
+\if@use@eepic@
+%    \end{macrocode}
+%    If the \packlass{eepic} package is not available, force the switch
+%    to false and warn the user.
+%    \begin{macrocode}
+  \IfFileExists{eepic.sty}{%
+    \RequirePackage{eepic}%
+  }{%
+    \@use@eepic@false
+    \ClassWarningNoLine{\@letteracdp}{%
+      Can't find the eepic package;\MessageBreak
+      option usePS ignored (converted to noPS)%
+    }%
+  }%
+\fi
+%    \end{macrocode}
+%
+%    \subsection{Main code}
+%
+%    ^^A ( paren match
+%    OK, boys, until now we have just set up a few things; now the real
+%    fun begins.~\mbox{:-)}  Oh, well, actually it will begin in a few lines:
+%    for now we have to do a little more bit of tedious work.~\mbox{:-(}
+%    ^^A ) paren match
+%
+%    \subsubsection{More initializations}
+%
+%    Some of the following initializations could have been put in the
+%    \emph{Initial code} section, but some others require that the code
+%    for the options have already been executed.
+%
+%    \begin{macro}{\date}
+%    We redefine "\date" in order to make the changes to the date local
+%    instead of global: this is useful if one of the letters has a date
+%    which is different from the other ones.  Since "\date" is a kernel
+%    command, an explicative comment is left in % the code too.
+%    \begin{macrocode}
+%% Command \date redefined to make changes to date local.
+\def\date#1{\def\@date{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\place}
+%    This command records the place where the letter is written (added
+%    in version~0.34): it is analogous to "\date".  Starting from
+%    version~0.34, this should be used instead of the optional argument
+%    of "\opening", "\makedate", etc.\ (however, the optional argument of
+%    those commands may still be used, for compatibility).  Note that the
+%    comma is added automatically, but only if the argument of "\place"
+%    is nonempty.
+%    \begin{macrocode}
+\newcommand*\place[1]{%
+  \ifx \@empty #1\@empty % if #1 is empty
+    \let\@place\@empty
+  \else
+    \def\@place{#1,}%
+  \fi
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Usual loading of the suitable \filedir{.clo} file; see the
+%    documentation of, \emph{e.g.}, the standard \packlass{letter}
+%    class for explanations about the following three lines of code.
+%    \begin{macrocode}
+\input{size1\@ptsize.clo}
+\setlength\lineskip{\p@}
+\setlength\normallineskip{\p@}
+%    \end{macrocode}
+%    \begin{macro}{\baselinestretch}
+%    This command can be redefined by the final user to obtain
+%    double-spaced, triple-spaced, etc.\ output.  See the
+%    \textsl{\LaTeX book} \cite[Subsection~C.3.2]{LaTeXbook}.
+%    \begin{macrocode}
+\renewcommand*\baselinestretch{}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\thelabel}
+%    The printed form of the \cnt{label} counter is changed to include
+%    also the number of the letter it refers to.  Note that we do not
+%    change "\p@label" (the prefix used only when printing
+%    \emph{references} to the counter), but actually the command used to
+%    print the counter itself.
+%    \begin{macrocode}
+\renewcommand*\thelabel{\theletter\@alph\c@label}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    The following are the usual constants used to represent typical
+%    penalty values; again, see the documentation of the standard
+%    classes.
+%    \begin{macrocode}
+\@lowpenalty   51
+\@medpenalty  151
+\@highpenalty 301
+%    \end{macrocode}
+%    We need five more constants of the same type, but with much
+%    higher penalty values.  They are used in the algorithm that takes
+%    care of folded letters.
+%    \begin{macrocode}
+\@fold@basepenalty 9000
+\@fold@lowpenalty  9101
+\@fold@medpenalty  9202
+\@fold@highpenalty 9303
+\@fold@toppenalty  9500
+%    \end{macrocode}
+%
+%    We now initialize the style parameters that contain the penalties
+%    inserted around the address blocks and the subject.  This values
+%    will never be used in practice, because usually the address blocks
+%    and the subject are wrapped up in a \ldots\env{presentation}
+%    environment, and these environments completely redefine the values
+%    of these style parameters.  The values given here will be used only
+%    when a \env{sender}, \env{addressee}, or \env{subject} environment
+%    is used without being wrapped in a presentation.  These values allow
+%    a page break without penalty before each of the blocks and at the
+%    end of the subject, mildly discourage a break after the address
+%    blocks, and discourage rather strongly a break at an "\and" or
+%    "\andcc" token.
+%    \begin{macrocode}
+\@b@frompenalty\z@
+\@i@frompenalty\@highpenalty
+\@e@frompenalty\@lowpenalty
+\@b@topenalty\z@
+\@i@topenalty\@highpenalty
+\@e@topenalty\@lowpenalty
+\@b@subjpenalty\z@
+\@e@subjpenalty\z@
+%    \end{macrocode}
+%    Unlike the preceding ones, the following style parameter is not
+%    redefined elsewhere.  It is the penalty inserted after
+%    presentations, and since a presentation typically ends with the
+%    subject, the following initialization seems quite natural.
+%    \begin{macrocode}
+\@e@prespenalty\@e@subjpenalty
+%    \end{macrocode}
+%
+%    \subsubsection{Page layout}
+%
+%    The first thing one could begin to find interesting is the code
+%    for setting up the page layout.  To help the reader to understand
+%    what is going on, fig.~\ref{fig:plo} summarizes the basic page
+%    layout parameters we are going to speak about.\footnote{If you are
+%    reading directly the comments in the \filedir{.dtx} file, instead of
+%    typesetting it with \LaTeX, you might find it difficult to follow
+%    the forthcoming discussion.}  This figure shows the parameters used
+%    in the case of an A5~sheet of paper: this allows to fit the entire
+%    figure on the page without having to scale it.
+%
+%    \begin{figure}[tbp]
+%      \centering
+%      \setlength{\unitlength}{1mm}
+%      \begin{picture}(108,200)(-10,0)
+%        \thinlines
+%        \put(-20,0)  {\line(1,0){148}}
+%        \put(-20,210){\line(1,0){148}}
+%        \put(-20,0)  {\line(0,1){210}}
+%        \put(128,0)  {\line(0,1){210}}
+%        \put(10,185){\makebox(88,10)[bl]{\makebox[88mm][s]{^^A
+%          \kern -1cm
+%          \setlength\unitlength{.625mm}^^A
+%          \begin{picture}(32,16)(-3,7.87)
+%            \thinlines
+%            \put(8,16){\oval(10,10)[l]}
+%            \put(8,11){\line(0,1){10}}
+%            \put(9,11){\framebox(3,20){}}
+%            \put(18,16){\oval(10,10)[r]}
+%            \put(18,11){\line(0,1){10}}
+%            \put(14,1){\framebox(3,20){}}
+%            \thicklines
+%            \put(8,16){\oval(16,16)[l]}
+%            \put(8,8){\line(1,0){5}}
+%            \put(13,24){\line(1,0){10}}
+%            \put(8,16){\oval(14,14)[l]}
+%            \put(8,9){\line(1,0){5}}
+%            \put(13,23){\line(1,0){10}}
+%            \put(18,8){\line(1,0){10}}
+%            \put(18,9){\line(1,0){10}}
+%          \end{picture}^^A
+%          \fontencoding{OT1}\selectfont
+%          \lhnss oordinamento dei {\lhbss D}\kern-.033333em ottorandi di
+%          {\lhbss P}\kern-.1em adova\enspace\hrulefill\kern-1cm
+%        }}}
+%        \put(10,40){\makebox(88,130)[tl]{\begin{minipage}[t]{88mm}
+%          \vrule height 10pt depth 0pt width 0pt \relax
+%          Text text text text text text text text text text text text
+%          text text text text text text text text text text text text.
+%        \end{minipage}}}
+%        \put(10,25){\makebox(88,3.514598035146)[tl]{\parbox[t]{88mm}{^^A
+%          \setlength{\parfillskip}{0pt}
+%          \noindent\rule{0pt}{10pt}\kern-1cm\hrulefill\kern-1cm\par
+%          \setlength{\baselineskip}{11pt}
+%          \fontencoding{OT1}\selectfont
+%          \hbox to \hsize{\hss\lhrm
+%            Coordinamento dei Dottorandi e dei Dottori di Ricerca
+%            dell'Universit\`{a} di Padova^^A
+%          \hss}
+%          \hbox to \hsize{\hss
+%            \lhit World Wide Web:\/
+%            \lhtt http://www.dei.unipd.it/\string~assdott/^^A
+%          \hss}
+%        }}}
+%        \linethickness{0.1pt}
+%        \put(-27,210){\line(1,0){17}}
+%        \put(-27,195){\line(1,0){125}}
+%        \put(-27,185){\line(1,0){142}}
+%        \put(-27,170){\line(1,0){142}}
+%        \put(-27,40) {\line(1,0){142}}
+%        \put(-27,25) {\line(1,0){142}}
+%        \put(10,25) {\line(0,1){192}}
+%        \put(98,25) {\line(0,1){192}}
+%        \put(20,185){\line(0,1){37}}
+%        \put(5,215) {\vector(1,0){5}}
+%        \put(10,215){\line(1,0){10}}
+%        \put(55,215){\vector(-1,0){35}}
+%        \put(55,215){\makebox(0,35)[br]{\strut\ttfamily\bslash @lh@left@margin}}
+%        \put(63,215) {\vector(1,0){35}}
+%        \put(63,215){\makebox(0,35)[bl]{\strut\ttfamily\bslash @lh@right@margin}}
+%        \put(98,215){\line(1,0){10}}
+%        \put(113,215){\vector(-1,0){5}}
+%        \put(108,25){\line(0,1){197}}
+%        \put(0,25)  {\line(0,1){12}}
+%        \put(-5,30){\vector(1,0){5}}
+%        \put(0,30) {\line(1,0){10}}
+%        \put(45,30){\vector(-1,0){35}}
+%        \put(45,30){\makebox(0,35)[br]{\strut\ttfamily\bslash @lh@right@margin}}
+%        \put(-15,35){\vector(1,0) {15}}
+%        \put(-5,35) {\vector(-1,0){15}}
+%        \put(-10,35){\makebox(0,0)[b]{\strut $2\,\mbox{cm}$}}
+%        \put(-20,200){\line(0,1){22}}
+%        \put(-10,220){\vector(1,0) {30}}
+%        \put(10,220) {\vector(-1,0){30}}
+%        \put(0,220){\makebox(0,0)[b]{\strut $4\,\mbox{cm}$}}
+%        \put(128,200){\line(0,1){22}}
+%        \put(113,220){\vector(1,0) {15}}
+%        \put(123,220){\vector(-1,0){15}}
+%        \put(118,220){\makebox(0,0)[b]{\strut $2\,\mbox{cm}$}}
+%        \put(113,195){\vector(0,1) {15}}
+%        \put(113,200){\vector(0,-1){15}}
+%        \put(113,197.5){\makebox(0,0)[l]{ $2.5\,\mbox{cm}$}}
+%        \put(113,175){\vector(0,1) {10}}
+%        \put(113,180){\vector(0,-1){10}}
+%        \put(113,177.5){\makebox(0,0)[l]{ $1.5\,\mbox{cm}$}}
+%        \put(113,30){\vector(0,1) {10}}
+%        \put(113,35){\vector(0,-1){10}}
+%        \put(113,32.5){\makebox(0,0)[l]{${}\ge1.5\,\mbox{cm}$}}
+%        \put(113,10){\vector(0,1) {15}}
+%        \put(113,15){\vector(0,-1){15}}
+%        \put(113,12.5){\makebox(0,0)[l]{ $2.5\,\mbox{cm}$}}
+%        \put(-25,200){\vector(0,1) {10}}
+%        \put(-25,205){\vector(0,-1){10}}
+%        \put(-25,202.5){\makebox(0,0)[r]{$\mbox{\ttfamily\bslash topmargin}+1\,\mbox{in}$ }}
+%        \put(-25,189){\vector(0,1) {6}}
+%        \put(-25,191){\vector(0,-1){6}}
+%        \put(-25,190){\makebox(0,0)[r]{{\ttfamily\bslash headheight} }}
+%        \put(-25,175){\vector(0,1) {10}}
+%        \put(-25,180){\vector(0,-1){10}}
+%        \put(-25,177.5){\makebox(0,0)[r]{{\ttfamily\bslash headsep} }}
+%        \put(-25,100){\vector(0,1) {70}}
+%        \put(-25,110){\vector(0,-1){70}}
+%        \put(-25,105){\makebox(0,0)[r]{{\ttfamily\bslash textheight} }}
+%        \put(-25,30){\vector(0,1) {10}}
+%        \put(-25,35){\vector(0,-1){10}}
+%        \put(-25,32.5){\makebox(0,0)[r]{{\ttfamily\bslash footskip} }}
+%        \put(-10,100){\vector(1,0) {20}}
+%        \put(0,100)  {\vector(-1,0){20}}
+%        \put(-5,100) {\makebox(0,0)[b]{\parbox[b]{4cm}{\centering
+%          \strut\texttt{\bslash oddsidemargin}\\
+%          or\\
+%          \texttt{\bslash evensidemargin}\\
+%          ${}+1\,\mbox{in}$\strut
+%        }}}
+%        \put(48,100){\vector(1,0) {50}}
+%        \put(60,100){\vector(-1,0){50}}
+%        \put(54,100){\makebox(0,0)[b]{\strut\ttfamily\bslash textwidth}}
+%      \end{picture}
+%      \caption{Basic page layout parameters}
+%      \label{fig:plo}
+%    \end{figure}
+%
+%    Before discussing the page layout parameters, let us make a brief
+%    digression to illustrate what we are trying to achieve and what
+%    difficulties we need to solve.  We would like that the seal and
+%    certain other details of the letterhead and the footer appeared in
+%    fixed positions with respect to the physical edges of the sheet:
+%    fig.~\ref{fig:plo} shows these fixed distances, explicitly given in
+%    centimeters, among the others, indicated by their symbolic name.
+%    This rises a little problem: we want to typeset the letterhead and
+%    the footer as standard \LaTeX\ headers and footers, but the
+%    subroutine for the header or the footer installed with a
+%    "\ps@"\ldots\ declaration is called inside a box of width
+%    "\textwidth" and aligned with the main body of text.  In other
+%    words, when typesetting the header, or the footer, one has no direct
+%    means to refer to the page boundaries: the only available reference
+%    points are the margins of the main body of text.  For this reason,
+%    it is necessary to precompute the offset from the text margins of
+%    the various points that we want to appear in fixed positions.  For
+%    instance, looking at fig.~\ref{fig:plo}: if we know that the left
+%    margin of the text runs exactly at \( 3\,\mbox{cm} \) from the left
+%    border of the sheet, and we want the left edge of the writing
+%    ``oordinamento dei Dottorandi di Padova'' to lie at exactly \(
+%    4\,\mbox{cm} \) from this border, we need to set the
+%    "\@lh@left@margin" parameter to \( 1\,\mbox{cm} \), to indicate that
+%    the left edge of the writing should lie \( 1\,\mbox{cm} \) to the
+%    right of the left text margin.
+%
+%    But this is only half of the story; the other half is best
+%    illustrated with an example.  Suppose you are typesetting on A4~paper,
+%    using 10 points fonts (these are precisely the settings chosen by
+%    default).  If you calculate the text margins and the text width
+%    following the recommendations given by the authors of \LaTeX\ for
+%    this particular combination of paper and font sizes, you will
+%    discover that the left margin of the main text runs at, say, \(
+%    4.2\,\mbox{cm} \) from the left border of the sheet.  (I~don't want
+%    to compute the exact value just now, since this is only an example,
+%    but I know that the actual value is very close to this, so the
+%    example is meaningful.)  If, according to what we have just said, you
+%    set "\@lh@left@margin" to \( -0.2\,\mbox{cm} \), you will end with
+%    the writing ``oordinamento\ldots'' that fails to be aligned with the
+%    main text by just \( 2\,\mbox{mm} \)---which is awful to see.
+%    Clearly, in a case like this it is better to foresee that
+%    "\@lh@left@margin" is going to receive a small value, and to adjust
+%    the left margin of the main body of text to \( 4\,\mbox{cm} \), so
+%    that "\@lh@left@margin" can be set to \( 0\,\mbox{pt} \).  This is
+%    just what the class does, and the final visual effect is, let
+%    me say, pretty good indeed\ldots
+%
+%    To sum up, the strategy for setting the page layout parameters is
+%    the following:
+%
+%    \begin{enumerate}
+%
+%    \item\label{plostep1}
+%    Compute the main text width and margins according to usual \LaTeX\
+%    recommendations.
+%
+%    \item\label{plostep2}
+%    Figure out whether the margins computed in step~\ref{plostep1} fall
+%    too close to some of the points of the letterhead that we want to
+%    stay in fixed position, and, if it is so, adjust them so that they
+%    are exactly aligned with those positions.
+%
+%    \item\label{plostep3}
+%    Allow the user to change the values computed in step~\ref{plostep2},
+%    in case (s)he needs to set the margins to some special value.
+%
+%    \item\label{plostep4}
+%     Compute the offset of those fixed points from one of the text
+%    margin (\emph{e.g.}, "\@lh@left@margin" in the example above), using
+%    whatever values for the margins are in effect after
+%    step~\ref{plostep3}, in such a way to be able to correctly position
+%    the abovementioned points using only the text margins as a reference.
+%
+%    \end{enumerate}
+%
+%    Of course, step~\ref{plostep3} occurs in the preamble; this means
+%    that step~\ref{plostep4} must be performed during the
+%    "\AtBeginDocument" hook.
+%
+%    As already said, the fixed distances of the layout design are all
+%    shown in fig.~\ref{fig:plo}; from this distances, from the relations
+%    shown in the figure, and from the additional information that the
+%    main body of text should be horizontally centered between the edges
+%    of the sheet, it is possible to deduce the values of almost all the
+%    basic page layout parameters once the value for "\textwidth" has
+%    been (cleverly) chosen.  Some of these parameters are readily
+%    readable: for instance, fig.~\ref{fig:plo} clearly states that
+%    "\headsep" should be equal to \( 1.5\,\mbox{cm} \); other parameters
+%    may require some computations, and may even not be completely
+%    determined: for instance, from the figure you see that \(
+%    "\topmargin"+"\headheight" = 2.5\,\mbox{cm}-1\,\mbox{in} \), but you
+%    cannot tell what the single values of "\topmargin" and "\headheight"
+%    are.  In the last case, the inherent uncertainty does no harm,
+%    because the "\headheight" parameter is not used to position any
+%    graphical element of the letterhead: it suffices to ensure that it
+%    allows enough room for the other, ordinary running heads; in
+%    practice, that there is room for a line of text in the largest
+%    supported font size (\emph{i.e.}, 12~points).  Setting "\headheight"
+%    to \( 1\,\mbox{cm} \) definitely satisfies this requisite, and has the
+%    nice additional aesthetic advantage that the virtual lines delimiting the
+%    head run exactly along the outer strokes of the ``C'' in the seal.
+%    (Note that decreasing or increasing the value of "\headheight" does
+%    not alter the dimensions of the seal: the dimensions of the seal are
+%    fixed, and the seal appears as a box of null width and height.)
+%
+%    We shall now discuss the parameters shown in fig.~\ref{fig:plo}
+%    one by one.  Of course, many of them are standard \LaTeX\ page
+%    layout parameters, and do not require particular explanations.
+%
+%    The first decision I took was to locate the lower right corner of
+%    the seal in a fixed position \( 4\,\mbox{cm} \) across and \(
+%    2.5\,\mbox{cm} \) down from the upper left corner of the page.  The
+%    value of \( 4\,\mbox{cm} \) was chosen because it was twice the
+%    design width of the seal; $2.5$~is the golden section of~$4$.  I then
+%    placed the upper margin of the main body of text \( 4\,\mbox{cm}
+%    \) from the upper edge of the paper.  Also, the rule found to the
+%    right of the letterhead extends up to a distance of \( 2\,\mbox{cm}
+%    \) from the right edge of the paper; the rule of the footer is
+%    aligned with that of the letterhead on the right, and on the left it
+%    extends to a symmetric distance.  From these fixed setting, one
+%    deduces the other parameters: let us see how.
+%
+%    \begin{description}
+%
+%    \renewcommand*\makelabel[1]{\hspace\labelsep\normalfont
+%      \texttt{\bslash #1}.}
+%
+%    \item[textwidth]
+%    This parameter is first of all initialized in the standard
+%    \filedir{.clo} files: this ensures that the standard \LaTeX\ initial
+%    value is used (cf.~step~\ref{plostep1} above).  Nevertheless, the
+%    value can be subsequently adjusted as explained in
+%    step~\ref{plostep2}, to achieve a better alignment with some points
+%    of the letterhead.
+%
+%    \item[oddsidemargin]
+%    This is set to \( \frac{1}{2}("\paperwidth"-"\textwidth") -
+%    1\,\mbox{in} \), to ensure that the main body of text is
+%    horizontally centered on the page.  Note that \LaTeX\ measures
+%    "\oddsidemargin" from the \TeX\ origin, and not from the left edge
+%    of the paper.
+%
+%    \item[evensidemargin]
+%    This is set equal to "\oddsidemargin".
+%
+%    \item[@lh@left@margin]
+%    This is set to \( 4\,\mbox{cm}-"\oddsidemargin"-1\,\mbox{in} \);
+%    this setting is done at ``"\begin{document}"-time''
+%    (cf.~step~\ref{plostep4} above), to allow the user to change
+%    "\oddsidemargin" in the preamble (cf.~step~\ref{plostep3} above).
+%    It can be useful to remark that the amount shown in
+%    fig.~\ref{fig:plo} is positive when measured according to the
+%    sign convention used internally by the code.
+%
+%    \item[@lh@right@margin]
+%    This is set to \( 2\,\mbox{cm}-"\oddsidemargin"-1\,\mbox{in} \);
+%    this setting is done at ``"\begin{document}"-time''
+%    (cf.~step~\ref{plostep4} above), to allow the user to change
+%    "\oddsidemargin" in the preamble (cf.~step~\ref{plostep3} above).
+%    It can be useful to remark that the amounts shown in
+%    fig.~\ref{fig:plo} are negative when measured according to the sign
+%    convention used internally by the code.
+%
+%    \item[topmargin]
+%    This is set to \( 2.5\,\mbox{cm}-1\,\mbox{in} \) (because \LaTeX\
+%    measures "\topmargin" from the \TeX\ origin, and not from the
+%    upper edge of the paper).
+%
+%    \item[headheight]
+%    This is set to \( 1\,\mbox{cm} \).
+%
+%    \item[headsep]
+%    This is set to \( 1.5\,\mbox{cm} \).
+%
+%    \item[textheight]
+%    To avoid underfull "\vbox"es when typesetting pages that contain
+%    no glue besides the "\baselineskip" glue (that usually has no
+%    ability to stretch or shrink), it is highly recommendable to
+%    set "\textheight" to an integer number of text lines, that is,
+%    to set it to \( "\topskip" + n\cdot"\baselineskip" \), where
+%    $n$~is a natural number.  We do this, choosing $n$ to be the
+%    largest natural number such that
+%    \begin{equation}
+%      "\topskip" + n\cdot"\baselineskip" \le "\paperheight"-8\,\mbox{cm}
+%      \mbox{.}
+%      \label{eq:textheight}
+%    \end{equation}
+%
+%    \item[footskip]
+%    This is set to \( "\paperheight" - "\textheight" -
+%    6.5\,\mbox{cm} \): this ensures that the baseline of the footer
+%    (along which the rule is traced) runs at \( 2.5\,\mbox{cm} \)
+%    from the bottom edge of the paper.
+%
+%    \end{description}
+%
+%    In the case of "\footskip", note that the baseline of the footer
+%    actually means\ldots\ the baseline of the footer!  I mean, normal
+%    footers (like, for instance, page numbers) are typeset with the
+%    baseline at exactly \( 2.5\,\mbox{cm} \) from the bottom edge of the
+%    paper; but the footer containing the address of the
+%    \emph{Coordinamento} is treated differently, in that it is the
+%    horizontal rule which is aligned with the baseline.
+%
+%    OK, after all this preliminary blather, we are now ready to return
+%    to the code.  Since we have already given many explanations, the
+%    following comments will be rather terse.
+%
+%    We begin to perform some of the initialization described above.
+%    \begin{macrocode}
+\setlength\headheight{1cm}
+\setlength\topmargin{1.5cm}
+\addtolength\topmargin{-1in}
+\setlength\headsep{1.5cm}
+%    \end{macrocode}
+%    The following settings pertaining to marginal notes and footnotes
+%    are simply copied from the standard \packlass{letter} class: we have
+%    no reason to change them.
+%    \begin{macrocode}
+\setlength\marginparsep {11\p@}
+\setlength\marginparpush{5\p@}
+\setlength\footnotesep{12\p@}
+\setlength{\skip\footins}{10\p@ plus 2\p@ minus 4\p@}
+%    \end{macrocode}
+%
+%    Everything we have been saying above was for \LaTeXe\footnote{This
+%    term should no longer be used, however: what was once known as
+%    \LaTeXe\ has now become \LaTeX\ \emph{tout-court}.}.  No attempt is
+%    made to support any users who happened to be still using the
+%    Palaeolithic \LaTeX~2.09: we simply honor the standard convention
+%    according to which certain basic page layout parameters must be set to
+%    fixed values in compatibility mode.  Note that the alignment of
+%    those certain special points of the letterhead to fixed positions
+%    will still work even in this case, but the placement of the main
+%    body of text will be awful, in the best hypothesis.  Note also that,
+%    in general, "\textheight" will not at all be of the form \(
+%    "\topskip" + n\cdot "\baselineskip" \).
+%    \begin{macrocode}
+\if@compatibility
+  \setlength\oddsidemargin{53pt}
+  \setlength\evensidemargin{53pt}
+  \setlength\marginparwidth{90pt}
+  \setlength\textwidth{365\p@}
+  \setlength\textheight{505\p@}
+  \setlength\footskip{25\p@}
+\else
+%    \end{macrocode}
+%
+%    Very well, now that the have get rid of that bothersome
+%    parenthesis of compatibility mode, we can go on with our
+%    initialization code.  We now take care of "\textwidth" and
+%    "\oddsidemargin".  These parameters have already been initialized in
+%    a \filedir{.clo} file---and this was step~\ref{plostep1}, see above.
+%    Now we take care of step~\ref{plostep2}.  Put
+%    \[
+%      "\@tempdima" = \textit{total\_left\_margin} :=
+%        {"\paperwidth"-"\textwidth"\over 2}
+%      \mbox{.}
+%    \]
+%    \begin{macrocode}
+  \setlength\@tempdima{\paperwidth}
+  \addtolength\@tempdima{-\textwidth}
+  \setlength\@tempdima{.5\@tempdima}
+%    \end{macrocode}
+%    If \( \textit{total\_left\_margin} < 3.25\,\mbox{cm} \), that is,
+%    if the left margin measured from the paper edge is too narrow, then
+%    we set "\oddsidemargin" to \( 3\,\mbox{cm} \), thereby aligning the
+%    left margin with the centre of the seal.
+%    \begin{macrocode}
+  \ifdim\@tempdima < 3.25cm % align to centre of logo
+    \setlength\oddsidemargin{3cm}
+%    \end{macrocode}
+%    If \( 3.25\,\mbox{cm} \le \textit{total\_left\_margin} <
+%    4.5\,\mbox{cm} \), that is, if the left margin measured from the paper
+%    edge is sufficiently close to the predetermined position of the right
+%    edge of the seal, then we align the former to the latter, by
+%    setting "\oddsidemargin" to~\( 4\,\mbox{cm} \).
+%    \begin{macrocode}
+  \else\ifdim\@tempdima < 4.5cm % align to right edge of logo
+    \setlength\oddsidemargin{4cm}
+%    \end{macrocode}
+%    In all other cases, we set "\oddsidemargin" to the computed
+%    $\textit{total\_left\_margin}$.
+%    \begin{macrocode}
+  \else % keep the computed margin
+    \setlength\oddsidemargin{\@tempdima}
+  \fi\fi
+%    \end{macrocode}
+%    Whatever value we have set "\oddsidemargin" to, we reset
+%    "\textwidth" according to it.
+%    \begin{macrocode}
+  \setlength\textwidth{\paperwidth}
+  \addtolength\textwidth{-2\oddsidemargin}
+%    \end{macrocode}
+%    Of course, we must not forget to subtract \( 1\,\mbox{in} \) from
+%    "\oddsidemargin": we shall do this later.
+%
+%    The following segment of code sets the width of marginal
+%    paragraphs (marginal notes).  We first try to use up all the
+%    margin, leaving only a gap of "\marginparsep" (already
+%    initialized above) on the text side, and of \( 7\,\mbox{mm} \)
+%    from the paper edge.  The latter should suffice with modern laser
+%    printers, but other printers might have more restrictive
+%    mechanical constraints that can affect their ability to print so
+%    close to the paper edge: let's hope everything works\ldots
+%    \begin{macrocode}
+  \setlength\marginparwidth{\oddsidemargin}
+  \addtolength\marginparwidth{-\marginparsep}
+  \addtolength\marginparwidth{-7mm}
+%    \end{macrocode}
+%    However, with some paper formats (\emph{e.g.}, with landscape
+%    orientation) the above setting may yield very wide marginal notes,
+%    which is undesirable.  Therefore, if the value just set exceeds one
+%    third of "\textwidth", we cut it down to this value, provided that
+%    the latter is at least \( 90\,\mbox{pt} \).
+%    \begin{macrocode}
+  \setlength\@tempdima{.33333\textwidth}
+  \ifdim\marginparwidth > \@tempdima
+    \ifdim\@tempdima < 90pt\else
+      \setlength\marginparwidth{\@tempdima}
+    \fi
+  \fi
+%    \end{macrocode}
+%
+%    All the main horizontal page layout parameters have been set.  We
+%    can now convert "\oddsidemargin" into \TeX's coordinate system: we
+%    did not do this before to ease other computations.  We also set
+%    "\evensidemargin".
+%    \begin{macrocode}
+  \addtolength\oddsidemargin{-1in}
+  \setlength\evensidemargin{\oddsidemargin}
+%    \end{macrocode}
+%
+%    We turn now to vertical parameters.  We set "\textheight"
+%    according to~\eqref{eq:textheight} and "\footskip" as stated above.
+%    First step:
+%    \[
+%      "\@tempdima" = \textit{max\_desired\_text\_height}
+%        := "\paperheight"-8\,\mbox{cm}
+%      \mbox{.}
+%    \]
+%    \begin{macrocode}
+  \setlength\@tempdima{\paperheight}
+  \addtolength\@tempdima{-8cm}
+  \setlength\footskip{\@tempdima}
+%    \end{macrocode}
+%    Remove the first line, which is only "\topskip" high:
+%    \begin{macrocode}
+  \addtolength\@tempdima{-\topskip}
+%    \end{macrocode}
+%    Set "\textheight" to the largest possible integer multiple of
+%    "\baselineskip":
+%    \begin{macrocode}
+  \divide\@tempdima\baselineskip
+  \@tempcnta=\@tempdima
+  \setlength\textheight{\@tempcnta\baselineskip}
+%    \end{macrocode}
+%    Put in again the first line:
+%    \begin{macrocode}
+  \addtolength\textheight{\topskip}
+%    \end{macrocode}
+%    "\footskip" is still equal to \( "\paperheight"-8\,\mbox{cm} \);
+%    finish its initialization (cf.~above):
+%    \begin{macrocode}
+  \addtolength\footskip{-\textheight}
+  \addtolength\footskip{1.5cm}
+%    \end{macrocode}
+%
+%    The following "\fi" goes with "\if@compatibility":
+%    \begin{macrocode}
+\fi
+%    \end{macrocode}
+%
+%    \begin{macro}{\computelongindentation}
+%    As explained above, "\longindentation" is a parameter that should
+%    set to roughly half the value of "\textwidth", with optional
+%    fine-tuning for better graphical results.  The setting is made
+%    by the "\computelongindentation" macro, which is available also
+%    to the final user: if (s)he alters the value of "\textwidth",
+%    then (s)he should also call this macro to update the value of
+%    "\longindentation".  The macro takes care of all the necessary
+%    fine-tuning.
+%    \begin{macrocode}
+\newcommand*\computelongindentation{%
+%    \end{macrocode}
+%    More precisely, "\longindentation" is set as follows: the first
+%    attempt is to set it equal to the width of the writing
+%    ``oordinamento dei Dottorandi di Padova'' ("\@oordinamento@box"
+%    is initialized below), because this makes for a great visual
+%    effect\ldots
+%    \begin{macrocode}
+  \setlength\@tempdima{\wd\@oordinamento@box}%
+  \setlength\longindentation{\@tempdima}%
+%    \end{macrocode}
+%    \ldots but this ideal value will only be retained if it falls within
+%    the closed range \( [\frac{1}{2}"\textwidth"-2.5\,\mbox{mm},
+%    \frac{1}{2}"\textwidth"+12.5\,\mbox{mm}] \), that is, sufficiently
+%    close to \( \frac{1}{2}"\textwidth" \) (which is the case for the
+%    most common page formats, like \opz{a4paper}); otherwise, \(
+%    \frac{1}{2}"\textwidth" \) will be used.
+%    \begin{macrocode}
+  \addtolength\@tempdima{2.5mm}%
+  \ifdim\@tempdima<.5\textwidth
+    \setlength\longindentation{.5\textwidth}%
+  \else
+    \addtolength\@tempdima{-12.5mm}%
+    \ifdim\@tempdima>.5\textwidth
+      \setlength\longindentation{.5\textwidth}%
+    \fi
+  \fi
+%    \end{macrocode}
+%    A final check is also made to ensure that "\longindentation" falls
+%    within the closed range \( [\frac{4}{10}"\textwidth",
+%    \frac{6}{10}"\textwidth"] \).
+%    \begin{macrocode}
+  \ifdim\longindentation<.4\textwidth
+    \setlength\longindentation{.5\textwidth}%
+  \else\ifdim\longindentation>.6\textwidth
+    \setlength\longindentation{.5\textwidth}%
+  \fi\fi
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    The following part of the code deals with initializations the have to be
+%    deferred until the "\begin{document}" hook.  The most complex of these is
+%    the check about the "\foldedheight" parameter.  Recall that this parameter,
+%    which is initialized to a default value by the code which handles the
+%    \ldots\opz{paper} options, can be altered by the user at any time, but has
+%    to be converted in an internal form afterwards; before making the
+%    conversion, we need to check that the value lies in the prescribed range.
+%    If this is not the case, we issue a warning and set the "\if@do@fold@"
+%    switch false: the "\@checkfoldedheight" macro, which will be defined below,
+%    takes care of this, and relies on the following two macros to provide two
+%    different types of warning.  They take two arguments, used to customize the
+%    message that the user will see: argument "#1" should be either the word
+%    ``short'' or the word ``tall'', argument "#2" should contain text giving
+%    further help.
+%
+%    In addition, the user can ``validate'' a new value assigned to
+%    "\foldedheight" at any point in the document, by means of the
+%    "\checkfoldedheight" command: this commands issues a warning also when the
+%    check is successful.
+%
+%    \begin{macro}{\@folding@ht@warn}
+%    This macro is invoked when the value of "\foldedheight" is found
+%    to be wrong in the check that is made during the "\AtBeginDocument"
+%    hook.
+%    \begin{macrocode}
+\@ifdefinable\@folding@ht@warn{\def\@folding@ht@warn#1#2{%
+  \ClassWarningNoLine{\@letteracdp}{%
+    \protect\foldedheight\space ignored:
+    it is too #1!\MessageBreak
+    (#2.)\MessageBreak
+    Folded letters will be shunned%
+  }%
+  \@do@fold@false
+}}%
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@folding@ht@NO}
+%    This macro is invoked when the value of "\foldedheight" is found to be
+%    wrong in a check being made by the "\checkfoldedheight" command.
+%    \begin{macrocode}
+\@ifdefinable\@folding@ht@NO{\def\@folding@ht@NO#1#2{%
+  \ClassWarning{\@letteracdp}{%
+    Bad value of \protect\foldedheight: it is too #1!\MessageBreak
+    (#2.)\MessageBreak
+    Therefore, at present folded letters are _shunned_;\MessageBreak
+    warning issued%
+  }%
+  \@do@fold@false
+}}%
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@folding@ht@OK}
+%    The following, instead, is the macro used to inform the user that
+%    the value of "\foldedheight" is correct.  It sets the "\if@do@fold@"
+%    switch to true, too.
+%    \begin{macrocode}
+\@ifdefinable\@folding@ht@OK{\def\@folding@ht@OK{%
+  \ClassWarning{\@letteracdp}{%
+    Checked \protect\foldedheight,
+    current value is acceptable.\MessageBreak
+    Therefore, at present folded letters are _allowed_;\MessageBreak
+    warning issued%
+  }%
+  \@do@fold@true
+}}%
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@checkfoldedheight}
+%    This is the internal version of the macro that checks the value of
+%    "\foldedheight"; it is invoked both by the "\checkfoldedheight" command and
+%    by the check that is made during the "\AtBeginDocument" hook.  The
+%    arguments have the following meaning:
+%    \begin{paramlist}
+%      \param
+%        command to execute if the value is bad (see below);\\
+%      \param
+%        command to execute if the value is OK\ (takes no arguments).
+%    \end{paramlist}
+%    The command passed in~\#1 must take two arguments, as follow:
+%    \begin{paramlist}
+%      \param
+%        either the word ``short'' or the word ``tall'';\\
+%      \param
+%        message giving additional information.
+%    \end{paramlist}
+%    Note that both "\@folding@ht@warn" and "\@folding@ht@NO" conform to this 
+%    calling protocol.
+%    \begin{macrocode}
+\@ifdefinable\@checkfoldedheight{\def\@checkfoldedheight#1#2{%
+%    \end{macrocode}
+%    To begin with, the value of "\foldedheight" must be positive in order for
+%    folded letters to be allowed.
+%    \begin{macrocode}
+  \ifdim\foldedheight>\z@
+%    \end{macrocode}
+%    Values greater than \( \frac{6}{10}"\paperheight" \) are rejected as too
+%    large.
+%    \begin{macrocode}
+    \ifdim\foldedheight>.6\paperheight
+      #1{tall}{%
+        It must not exceed 0.6\protect\paperheight
+      }%
+%    \end{macrocode}
+%    "\@folding@ht" holds the height of the folded flap measured from the top
+%    margin \emph{of the text}.
+%    \begin{macrocode}
+    \else
+      \setlength\@folding@ht{\foldedheight}%
+      \addtolength\@folding@ht{-1in}%
+      \addtolength\@folding@ht{-\topmargin}%
+      \addtolength\@folding@ht{-\headheight}%
+      \setlength\@lh@folding@ht{-\@folding@ht}%
+      \addtolength\@folding@ht{-\headsep}%
+%    \end{macrocode}
+%    If the height of the folded flap measured from the top margin of the text
+%    is less than $2.5\,\mbox{cm}$, it is rejected as well as too small.
+%    \begin{macrocode}
+      \ifdim\@folding@ht<2.5cm
+        #1{short}{%
+          At least 2cm _of_text_ and 0.5cm of margin\MessageBreak
+          must be allowed above the folding%
+        }%
+%    \end{macrocode}
+%    Otherwise, the value of "\foldedheight" is acceptable.
+%    \begin{macrocode}
+      \else
+        \setlength\@above@folding@margin{1cm}%
+        \setlength\@above@folding@shrink{5mm}%
+        \setlength\@below@folding@skip{5mm}%
+        \dimen4 .5\baselineskip
+        \dimen@ \@folding@ht
+        \advance\dimen@ \@below@folding@skip
+        \advance\dimen@ -\topskip
+        \dimen@ii -\dimen@
+        \divide\dimen@ \dimen4
+        \count@ \dimen@
+        \advance\dimen@ii \count@\dimen4%
+        \addtolength\@below@folding@skip{\dimen@ii}%
+        \addtolength\@folding@ht{-\@above@folding@margin}%
+%    \end{macrocode}
+%    Note that the command passed in~\#2 \emph{must} take care of setting the
+%    "\if@do@fold@" switch to ``true''.
+%    \begin{macrocode}
+        #2%
+%    \end{macrocode}
+%    End of "\ifdim\@folding@ht<2.5cm":
+%    \begin{macrocode}
+      \fi
+%    \end{macrocode}
+%    End of "\ifdim\foldedheight>.6\paperheight":
+%    \begin{macrocode}
+    \fi
+%    \end{macrocode}
+%    When \( "\foldedheight" \le 0 \), folded letters are silently shunned:
+%    \begin{macrocode}
+  \else
+    \@do@fold@false
+  \fi
+}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\checkfoldedheight}
+%    This is the user-level command, for checking the value of "\foldedheight"
+%    at the user's request (as opposed to checking it at the "\AtBeginDocument"
+%    hook).
+%    \begin{macrocode}
+\newcommand*\checkfoldedheight{%
+  \@checkfoldedheight\@folding@ht@NO\@folding@ht@OK
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Now we perform step~\ref*{plostep4} (see \hyperref[plostep4]{above}) of 
+%    our ``strategy for setting the page layout parameters'':
+%    \begin{macrocode}
+\AtBeginDocument{%
+  \setlength\@lh@left@margin{4cm}%
+  \addtolength\@lh@left@margin{-1in}%
+  \addtolength\@lh@left@margin{-\oddsidemargin}%
+  \setlength\@lh@right@margin{\@lh@left@margin}%
+  \addtolength\@lh@right@margin{-2cm}%
+%    \end{macrocode}
+%    This is the ``"\begin{document}"'' check for the value of "\foldedheight":
+%    it calls "\@folding@ht@warn" if the current value is bad, and simply sets
+%    the "\if@do@fold@" switch to ``true'' (without giving any warning) if it
+%    is~OK\@.
+%    \begin{macrocode}
+  \@checkfoldedheight\@folding@ht@warn\@do@fold@true
+  \let\@folding@ht@warn\@undefined
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@oordinamento@box}
+%    \changes{0.36d}{2018 Feb 08}{Added selection of the OT1 font encoding to 
+%      the code that presets the b/w version.}^^A
+%    The reason for typesetting this box here was (in 1999) to save compilation
+%    time.  In version 0.36d, "\fontencoding{OT1}\selectfont" has been added.
+%    \begin{macrocode}
+\sbox\@oordinamento@box{%
+  \fontencoding{OT1}\selectfont\@lh@nss
+  oordinamento dei {\@lh@bss D}\kern-.033333em ottorandi di
+  {\@lh@bss P}\kern-.1em adova\enspace
+}
+%    \end{macrocode}
+%    \end{macro}
+%    Now that we know the width of "\@oordinamento@box", we can now compute the
+%    value of "\longindentation":
+%    \begin{macrocode}
+\computelongindentation
+%    \end{macrocode}
+%
+%    Uncommented code starts here.
+%    \begin{macrocode}
+\newcommand*\standardvertspaces{%
+  \setlength\aboveaddressvspace       {\medskipamount}%
+  \@msetlength\andaddressvspace       {2}{\medskipamount}%
+  \@msetlength\belowaddressvspace     {3}{\medskipamount}%
+  \setlength\abovesubjectvspace       {\medskipamount}%
+  \setlength\presubjectvspace         {\medskipamount}%
+  \@msetlength\belowsubjectvspace     {3}{\medskipamount}%
+  \@msetlength\abovesignaturevspace   {6}{\medskipamount}%
+  \setlength\abovesignatureshortvspace{\bigskipamount}%
+  \setlength\belowsignaturevspace     {\bigskipamount}%
+  \@msetlength\belowpresentationvspace{3}{\medskipamount}%
+}
+\setlength\senderindentation   {\z@}
+\setlength\senderwidth         {\textwidth}
+\setlength\addresseeindentation{\z@}
+\setlength\addresseewidth      {\textwidth}
+\setlength\signatureindentation{\z@}
+\setlength\signaturewidth      {\textwidth}
+\standardvertspaces
+%    \end{macrocode}
+%
+%    \subsubsection{Page styles}
+%
+%    \begin{macrocode}
+\newcommand*{\automark}{\let\@mkboth\markboth}
+\newcommand*{\usermark}{\let\@mkboth\@gobbletwo}
+\automark % default is to put page no. and addressee in the header
+%% We need to change even the definition of the standard page styles.
+\def\ps@empty{%
+  \let\@oddhead\@empty
+  \let\@evenhead\@empty
+  \let\@oddfoot\@empty
+  \let\@evenfoot\@empty
+}
+\def\ps@plain{%
+  \let\@oddhead\@empty
+  \let\@evenhead\@empty
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@firstpage{%
+  \let\@oddhead\@empty
+  \let\@evenhead\@empty
+  \let\@oddfoot\@first@foot
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@foldedpage{%
+  \def\@oddhead{\hfill\@folding@tag}%
+  \let\@evenhead\@empty
+  \let\@oddfoot\@first@foot
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@letterhead{%
+  \let\@oddhead\@cdp@head
+  \let\@evenhead\@empty
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@firstletterhead{%
+  \let\@oddhead\@cdp@head
+  \let\@evenhead\@empty
+  \let\@oddfoot\@cdp@foot
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@foldedletterhead{%
+  \def\@oddhead{\@cdp@head\@folding@tag}%
+  \let\@evenhead\@empty
+  \let\@oddfoot\@cdp@foot
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@logo{%
+  \def\@oddhead{\@cdp@logo\hfill}%
+  \let\@evenhead\@empty
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@headings{%
+  \automark
+  \let\@oddhead\@r@head
+  \let\@evenhead\@l@head
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@logoheadings{%
+  \automark
+  \def\@oddhead{\@cdp@logo\@r@head}%
+  \let\@evenhead\@l@head
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@myheadings{%
+  \usermark
+  \let\@oddhead\@r@head
+  \let\@evenhead\@l@head
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@logomyheadings{%
+  \usermark
+  \def\@oddhead{\@cdp@logo\@r@head}%
+  \let\@evenhead\@l@head
+  \let\@oddfoot\@centred@folio
+  \let\@evenfoot\@centred@folio
+}
+\def\ps@letterheadnpn{%
+  \let\@oddhead\@cdp@head
+  \let\@evenhead\@empty
+  \let\@oddfoot\@empty
+  \let\@evenfoot\@empty
+}
+\def\ps@logonpn{%
+  \def\@oddhead{\@cdp@logo\hfill}%
+  \let\@evenhead\@empty
+  \let\@oddfoot\@empty
+  \let\@evenfoot\@empty
+}
+\@ifdefinable\@centred@folio{\def\@centred@folio{%
+  \reset@font\hfil\thepage\hfil
+}}
+\@ifdefinable\@l@head{\def\@l@head{%
+  \reset@font\slshape\hfil\ignorespaces\leftmark\unskip\/\hfil
+}}
+\@ifdefinable\@r@head{\def\@r@head{%
+  \reset@font\slshape\hfil\ignorespaces\rightmark\unskip\/\hfil
+}}
+\@ifdefinable\@first@foot{\def\@first@foot{%
+  \reset@font
+  \raisebox{-24\p@}[\z@]{%
+    \hb@xt@\textwidth{%
+      \ifcase \@ptsize\relax
+        \normalsize
+      \or
+        \small
+      \or
+        \footnotesize
+      \fi
+      \thesenderlocation \hfill \thesenderphone
+    }%
+  }\hss
+}}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@folding@tag}
+%    Invoked by the macros that implement the ``folded'' page styles,
+%    more precisely by those which draw the header, to draw the small sign
+%    that marks the point where the sheet should be folded.
+%    \begin{macrocode}
+\@ifdefinable\@folding@tag{\def\@folding@tag{%
+  \if@do@fold@
+    \raisebox{\@lh@folding@ht}[\z@][\z@]{%
+      \makebox[\z@][l]{%
+%    \end{macrocode}
+%    Vers.~0.36: new and more robust way of computing the horizontal position.
+%    \begin{macrocode}
+        \dimen@ \paperwidth
+        \advance \dimen@ -1in%
+        \advance \dimen@ -\oddsidemargin
+        \advance \dimen@ -\textwidth
+        \advance\dimen@ -1cm%
+%    \end{macrocode}
+%    End of change.
+%    \begin{macrocode}
+        \kern\dimen@ \vbox{%
+%    \end{macrocode}
+%    Vers.~0.36: change to support the new "\foldingtagrule" user-level command
+%    and the use of color.
+%    \begin{macrocode}
+          \color@begingroup
+          \foldingtagrule
+          \color@endgroup
+%    \end{macrocode}
+%    End of change.
+%    \begin{macrocode}
+        }%
+      }%
+    }%
+  \fi
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\foldingtagrule}
+%    Vers.~0.36 (2015 Feb~08): new command, redefinable by the user, 
+%    to draw the tag.  It permits customization of the latter.
+%    It should take up no vertical space in total
+%    (\emph{i.e.}, it should backspace).
+%    \begin{macrocode}
+\newcommand*\foldingtagrule{%
+  \kern -.1\p@
+  \hrule \@height .1\p@ \@depth .1\p@ \@width 5mm%
+  \kern -.1\p@
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\CDPFactoryFoldingTagRule}
+%    Back up of the above.  Should \emph{not} be redefined!
+%    \begin{macrocode}
+\@ifdefinable\CDPFactoryFoldingTagRule{
+  \let \CDPFactoryFoldingTagRule = \foldingtagrule
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \subsubsection{Macros for drawing the CDP\ seal}
+%
+%    There are essentially two reasons for which I~cannot get rid of these:
+%    \begin{enumerate}
+%      \renewcommand*{\theenumi}{{\normalfont (\textit{\roman{enumi}})}}
+%      \renewcommand*{\labelenumi}{\theenumi}
+%      \item
+%        sentimental reasons;
+%      \item
+%        we must ensure that it is still possible to typeset the legacy 
+%        documentation, which uses the letterhead of the \emph{Coordinamento}.
+%    \end{enumerate}
+%    In 1999, people of the \emph{Coordinamento} used the \Bundle\ on a variety
+%    of personal computers (mostly Macintoshes) that were often connected to
+%    printers lacking a PostScript interpreter; it was therefore essential that
+%    the CDP\ seal could be drawn relying exclusively on those capabilities of
+%    the \env{picture} environment that are implemented without having recourse
+%    to any particular driver (\emph{e.g.}, \texttt{dvips}).  This had indeed
+%    been a fundamental principle in the design of the logotype.
+%
+%    \begin{macro}{\@logo@box@base}
+%    This holds the main part of the CDP\ seal; more precisely, that part that
+%    appears both in the \ldots\sty{letterhead} and in the \sty{logo}\ldots page
+%    styles.
+%    \begin{macrocode}
+\savebox\@logo@box@base[\z@][r]{\setlength\unitlength{.625mm}%
+  \begin{picture}(32,16)(-3,7.87)%
+    \put(8,16){\oval(10,10)[l]}%
+    \put(8,11){\line(0,1){10}}%
+    \put(9,11){\framebox(3,20){}}%
+    \put(18,16){\oval(10,10)[r]}%
+    \put(18,11){\line(0,1){10}}%
+    \put(14,1){\framebox(3,20){}}%
+    \thicklines
+    \put(8,16){\oval(16,16)[l]}%
+    \put(8,8){\line(1,0){5}}%
+    \put(13,24){\line(1,0){10}}%
+    \put(8,16){\oval(14,14)[l]}%
+    \put(8,9){\line(1,0){5}}%
+    \put(13,23){\line(1,0){10}}%
+  \end{picture}%
+}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@logo@box@addS}
+%    This holds the part of the CDP\ seal that should be added to the part
+%    contained in "\@logo@box@base" to obtain the seal as it appears in the
+%    \sty{logo}\ldots page styles.
+%    \begin{macrocode}
+\savebox\@logo@box@addS[\z@][r]{\setlength\unitlength{.625mm}%
+  \begin{picture}(32,16)(-3,7.87)%
+    \thicklines
+    \put(18,8){\line(1,0){8}}%
+    \put(18,9){\line(1,0){8}}%
+  \end{picture}%
+}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@logo@box@addL}
+%    This holds the part of the CDP\ seal that should be added to the part
+%    contained in "\@logo@box@base" to obtain the seal embedded in the
+%    \ldots\sty{letterhead} page styles.
+%    \begin{macrocode}
+\savebox\@logo@box@addL[\z@][r]{\setlength\unitlength{.625mm}%
+  \begin{picture}(32,16)(-3,7.87)%
+    \thicklines
+    \put(18,8){\line(1,0){10}}%
+    \put(18,9){\line(1,0){10}}%
+  \end{picture}%
+}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@logo@overlay}
+%    Utility macro, that typesets the part of the logo that is common to the
+%    letterhead too.  Note the final "\copy" primitive, that lacks its argument.
+%    \begin{macrocode}
+\@ifdefinable\@logo@overlay{\def\@logo@overlay{%
+  \kern\@lh@left@margin
+  \copy\@logo@box@base \copy
+}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@cdp@logo}
+%    This macro is invoked by "\ps@"\ldots\ macros to typeset the seal.
+%    \begin{macrocode}
+\@ifdefinable\@cdp@logo{\def\@cdp@logo{%
+  \@logo@overlay\@logo@box@addS
+}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@cdp@head}
+%    This macro is invoked by "\ps@"\ldots\ macros to typeset the letterhead.  
+%    Note that it fills up the current horizontal box.
+%    \begin{macrocode}
+\@ifdefinable\@cdp@head{\def\@cdp@head{%
+  \@logo@overlay\@logo@box@addL
+  \copy\@oordinamento@box \hrulefill \kern\@lh@right@margin
+}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@name@and@WWW@box}
+%    This holds the footer used in the \sty{firstletterhead} and
+%    \sty{foldedletterhead} page styles, which contains the full name of
+%    the \emph{Coordinamento} and its web address.
+%    \changes{0.36d}{2018 Feb 08}{Added selection of the OT1 font encoding to 
+%      the code that presets the b/w version.}^^A
+%    Vers.~0.36d: added "\fontencoding{OT1}\selectfont".
+%    \begin{macrocode}
+\setbox\@name@and@WWW@box = \vtop{%
+  \baselineskip 11\p@
+  \fontencoding{OT1}\selectfont
+  \hb@xt@\z@{\hss \@lh@rm\Coordinamento \hss}%
+  \hb@xt@\z@{%
+    \hss
+    \@lh@it World Wide Web:\/
+    \@lh@tt \CoordinamentoWWW
+    \hss
+  }%
+}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\@cdp@foot}
+%    This macro is invoked by "\ps@"\ldots\ macros to typeset the footer
+%    associated with the letterhead.  It draws a horizontal rule that runs along
+%    the baseline of the footer (the same baseline on which page numbers would
+%    lie) starting from a distance of $-"\@lh@right@margin"$ into the left
+%    margin and stopping at an equal distance into the right margin, and then
+%    appends under this rule the saved contents of "\@name@and@WWW@box",
+%    horizontally centered with "\hfil".
+%    \begin{macrocode}
+\@ifdefinable\@cdp@foot{\def\@cdp@foot{%
+  \reset@font
+  \setlength\@tempdima{\textwidth}%
+  \addtolength\@tempdima{-2\@lh@right@margin}%
+  \hss\parbox[t]{\@tempdima}{%
+    \parfillskip\z@skip
+    \noindent\hrulefill\@@par
+    \baselineskip 11\p@
+    \hb@xt@\hsize{\hfil\copy\@name@and@WWW@box\hfil}%
+  }\hss
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \subsubsection{\textquotedblleft Letter-making\textquotedblright\ environments}
+%
+%    We start with the commands that set the sender's data.
+%
+%    \begin{macro}{\name}
+%    The sender's name (\emph{e.g.}, "\name{R.~J.~Drofnats}").
+%    \begin{macrocode}
+\newcommand*\name     [1]{\def\thesendername{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\signature}
+%    The sender's signature (\emph{e.g.}, 
+%    "\signature{R.~J.~Drofnats\\Professor}").
+%    \begin{macrocode}
+\newcommand \signature[1]{\def\thesendersignature{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\address}
+%    The sender's address, \emph{including} the name.
+%    \begin{macrocode}
+\newcommand \address  [1]{\def\thesenderaddress{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\location}
+%    The sender's location (\emph{e.g.}, floor, room number\ldots).
+%    \begin{macrocode}
+\newcommand \location [1]{\def\thesenderlocation{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%    \begin{macro}{\telephone}
+%    The sender's telephone number.
+%    \begin{macrocode}
+\newcommand*\telephone[1]{\def\thesenderphone{#1}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\makelabels}
+%    \changes{0.36}{2015 Feb 08}{Added new instruction
+%      \texttt{\protect\bslash @making@labels@true}.}^^A
+%    The "\makelabels" command now sets the "\if@making@labels@" switch.
+%    \begin{macrocode}
+\newcommand*\makelabels{%
+  \@making@labels@true
+  \AtBeginDocument{%
+     \def\@beginlabels{\begin{labels}}%
+     \def\@beginlabelgroup{\begin{labelgroup}}%
+     \let\@mlabel\basemlabel
+     \def\@endlabelgroup{\end{labelgroup}}%
+     \def\@endlabels{\end{labels}}%
+     \if@filesw
+       \immediate\write\@mainaux{\string\@beginlabels}\fi}%
+  \AtEndDocument{%
+     \if@filesw\immediate\write\@mainaux{\string\@endlabels}\fi}}
+\@onlypreamble\makelabels
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\cleardoubleemptypage}
+%    Similar to "\cleardoublepage", but inserts pages with \sty{empty} page
+%    style.
+%    \begin{macrocode}
+\newcommand*\cleardoubleemptypage{\par
+  \onecolumn
+  \if@twoside \ifodd\c@page \else
+    \thispagestyle{empty}\null\newpage
+  \fi\fi
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@safe@space}
+%    This macro inserts \#1 in the current horizontal lists; if it contributes
+%    a (strictly) positive width, it also inserts~\#2.  Usually \#1 is a
+%    certain string, and \#2 is a spacing command that one wants to emit (if
+%    and) only if the string is nonempty.
+%    \begin{macrocode}
+\@ifdefinable\@safe@space{\def\@safe@space#1#2{%
+  \setbox\z@\hbox{\ignorespaces #1\unskip}%
+  \ifdim\wd\z@>\z@
+    \unhbox\z@ #2%
+  \else
+    \unhbox\z@
+  \fi
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{environment}{baseletter}
+%    \changes{0.31}{2001 Dec 01}{Reintroduced the first mandatory argument
+%      to hold local initializations.}^^A
+%    All the ``letter-making'' environments are based upon this one, which is
+%    the lowest-level one.  Its purpose is to take the basic actions that are
+%    needed to begin and end every kind of letter.  In this version of the code
+%    it takes two arguments (this has changed several times among different
+%    releases), which are meant to contain code that performs any custom
+%    initialization required by the higher-level environments (or by the user,
+%    if this environment is called directly by the user).  The code passed
+%    in~"#1" is executed before the core initializations provided by
+%    "baseletter", but inside the group implied by this environment; the code
+%    passed in~"#2" is executed as the last thing (just before
+%    "\@cdp@begin@letter@hook").  Other arguments will be picked up by the
+%    "\x@baseletter" or "\y@baseletter" macro.
+%    \begin{macrocode}
+\newenvironment{baseletter}[2]{%
+  #1%
+%    \end{macrocode}
+%    Save~"#2" in a token register for later execution:
+%    \begin{macrocode}
+  \@lett@decl{#2}%
+%    \end{macrocode}
+%    Obvious initializations; note that "\cleardoubleemptypage" calls
+%    "\onecolumn".
+%    \changes{0.36d}{2018 Feb 08}{Added \texttt{\protect\bslash global} before 
+%      \texttt{\protect\bslash c@page\protect\bslash @ne}.}^^A
+%    Vers.~0.36d: added "\global" in front of "\c@page\@ne".
+%    \begin{macrocode}
+  \cleardoubleemptypage
+  \global\c@page\@ne
+  \refstepcounter{letter}%
+  \typeout{\lettername \space \number\c@letter}%
+  \interlinepenalty 200 % smaller than the TeXbook value
+  \parskip\medskipamount
+%    \end{macrocode}
+% Set "\parindent" according to the option specified by the user.
+%    \begin{macrocode}
+  \ifx\@indent@pref L\else
+    \ifx\@indent@pref N%
+      \setlength\parindent{\z@}%
+    \else
+      \ifdim .1\textwidth>2pc
+        \setlength\parindent{.1\textwidth}%
+      \else
+        \setlength\parindent{2pc}%
+      \fi
+    \fi
+  \fi
+%    \end{macrocode}
+%    Continue initialization in two different ways, according to the
+%    presence or not of the first optional argument.
+%    \begin{macrocode}
+  \@ifnextchar[\x@baseletter\y@baseletter % ] bracket matching
+}{%
+%    \end{macrocode}
+%    Code for ending letters.  "\stopletter" is a hook reserved to the
+%    user; it is executed \emph{before} the last page of the letter is
+%    finished off.
+%    \begin{macrocode}
+  \stopletter
+%    \end{macrocode}
+%    Now ensure vertical mode and add a zero-cost page break \emph{above}
+%    the vertical glue (possibly) present at the end of the page: this
+%    allows to discard the glue after the signature if this is needed to
+%    fit the letter in the page, even if "\stopbreaks" is in effect after
+%    the signature.  Should this be a ``"-\@M"''-cost page break instead?
+%
+%    (2015 Feb~08, vers.~0.36: definitely \emph{no}, since that would stretch 
+%    out the last page of the letter!  It was fortunate we didn't dare change
+%    it in previous releases!)
+%    \begin{macrocode}
+  \@@par\addpenalty\z@
+  \clearpage
+%    \end{macrocode}
+%    The following is a hook reserved to extensions of the
+%    \packlass{letteracdp} class; it is used, for instance, by
+%    \packlass{articoletteracdp}.  Note that it is executed \emph{after}
+%    ejecting the last page of the letter.
+%    \changes{0.36d}{2018 Feb 08}{Changed the name of the (former) 
+%      \texttt{\protect\bslash @end@letter@hook} hook to
+%      \texttt{\protect\bslash @cdp@end@letter@hook}.}^^A
+%    (Vers.~0.36d: changed name, added \texttt{@cdp} prefix.)
+%    \begin{macrocode}
+  \@cdp@end@letter@hook
+%    \end{macrocode}
+%    Write to the \filedir{.aux} file the data for the address labels.
+%    This is rather tricky because we can have multiple addressees
+%    \emph{and} multiple senders
+%    \changes{0.36}{2015 Feb 08}{Added check for the
+%      \texttt{\protect\bslash if@making@labels@} switch before writing to the
+%      \protect\filedir{.aux} file unneeded information for generating the
+%      address labels.}^^A
+%    (v.~0.36: note the new check for "\if@making@labels@", in order to write
+%    to the \filedir{.aux} file the information about the address labels
+%    only when it is actually needed).
+%    \begin{macrocode}
+  \if@filesw \if@making@labels@
+    \begingroup
+%    \end{macrocode}
+%    Ensure that "\\", "~" and "\protect"'ed tokens are written literally
+%    instead of being expanded:
+%    \begin{macrocode}
+      \let\\\relax
+      \let ~\relax
+      \let\protect\@unexpandable@protect
+%    \end{macrocode}
+%    ^^A { brace match
+%    The following hack causes "\and" (and "\andcc") to expand into
+%    ``"}\@gobble{"''.
+%    ^^A } brace match
+%    \begin{macrocode}
+      \def\and{%
+        \iffalse{\fi}\expandafter\@gobble\expandafter{\iffalse}\fi
+      }%
+      \let\andcc\and
+%    \end{macrocode}
+%    "\returnaddress" contains the addresses of the senders, separated by
+%    "\and"; thanks to the above hack, only the first is saved into
+%    "\@cdp@reserved", and the others are "\@gobble"'d.
+%    \begin{macrocode}
+      \edef\@cdp@reserved{{\returnaddress}}%
+%    \end{macrocode}
+%    We now cope with "\and"'s and "\andcc"'s inside "\theaddresseeaddress":
+%    we write them to the \filedir{.aux} file as
+%    ^^A { brace match
+%    ``"}"\,\meta{LF}\,"\@mlabel{"^^A
+%    \( \langle\mbox{\itshape expansion of\/ } "\@cdp@reserved"\,\rangle \)^^A
+%    "}{"'',
+%    ^^A } brace match
+%    \emph{i.e.}, for what we have just said, as
+%    ^^A { brace match
+%    ``"}"\,\meta{LF}\,"\@mlabel{"\meta{address of 1st~sender}"}{"''.
+%    ^^A } brace match
+%    \begin{macrocode}
+      \def\and{%
+        \iffalse{\fi}^^J%
+        \string\@mlabel{\@cdp@reserved}{\iffalse}\fi
+      }%
+      \let\andcc\and
+%    \end{macrocode}
+%    We are now ready to write out the correct sequence of commands,
+%    \emph{e.g.}:
+%    \begingroup
+%      \fontsize{9}{11}\selectfont
+%      \zerolistvertspaces
+%      \begin{flushleft}
+%        "\@beginlabelgroup"\\
+%        "\@mlabel{"\meta{1st sender}"}{"\meta{1st addressee}"}"\\
+%        "\@mlabel{"\meta{1st sender}"}{"\meta{2nd addressee}"}"\\
+%        "\@mlabel{"\meta{1st sender}"}{"\meta{3rd addressee}"}"\\
+%        \ldots\\
+%        "\@endlabelgroup"\\
+%      \end{flushleft}
+%    \endgroup
+%    \begin{macrocode}
+      \immediate\write\@auxout{%
+        \string\@beginlabelgroup ^^J%
+        \string\@mlabel
+          {\@cdp@reserved}{\theaddresseeaddress}^^J%
+        \string\@endlabelgroup
+      }%
+    \endgroup
+%    \end{macrocode}
+%    Vers.~0.36: note the additional "\fi" to go with the new
+%    "\if@making@labels@".
+%    \begin{macrocode}
+  \fi \fi
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    Back to uncommented code.
+%    \begin{macrocode}
+\@ifdefinable\x@baseletter{\long\def\x@baseletter[#1]#2{%
+  \def\theaddresseename{#1}%
+  \def\theaddresseeaddress{#2}%
+  \@baseletter
+}}
+\@ifdefinable\y@baseletter{\long\def\y@baseletter#1{%
+  \@cut@andcc #1\andcc\@@@
+  \def\theaddresseeaddress{#1}%
+  \@baseletter
+}}
+\newcommand\@baseletter[1][]{%
+  \def\thesubject{#1}%
+  \if@twoside
+    \@mkboth{%
+      \noexpand\@safe@space\noexpand\headtoname\noexpand\enspace
+      \ignorespaces\theaddresseename\unskip \hfill \noexpand\@date
+    }{%
+      \noexpand\@date \hfill
+      \noexpand\@safe@space\noexpand\headtoname\noexpand\enspace
+      \ignorespaces\theaddresseename % \unskip put by \@?@head
+    }%
+  \else
+    \@mkboth{}{%
+      \noexpand\@safe@space\noexpand\headtoname\noexpand\enspace
+      \ignorespaces\theaddresseename\unskip \hfill \noexpand\@date
+    }%
+  \fi
+  \the\@lett@decl
+  \@cdp@begin@letter@hook
+}
+\@ifdefinable\@cut@andcc{\long\def\@cut@andcc#1\andcc#2\@@@{%
+  \@cut@and #1\and\@@@%
+}}
+\@ifdefinable\@cut@and{\long\def\@cut@and#1\and#2\@@@{%
+  \@cut@nl #1\\\@@@%
+}}
+\@ifdefinable\@cut@nl{\long\def\@cut@nl#1\\#2\@@@{%
+  \@cut@par #1\par\@@@%
+}}
+\@ifdefinable\@cut@par{\long\def\@cut@par#1\par#2\@@@{%
+  \def\theaddresseename{#1}%
+}}
+\newcommand*\stopbreaks{%
+  \interlinepenalty\@M
+  \def\par{\ifvmode\else\@@par\nobreak\fi}%
+  \let\\\@nobreakcr
+  \let\vspace\@nobreakvspace
+}
+\DeclareRobustCommand\@nobreakvspace
+   {\@ifstar\@vspacer\@nobreakvspacex}
+\@ifdefinable\@nobreakvspacex{\def\@nobreakvspacex#1{%
+  \ifvmode
+    \nobreak
+    \vskip #1%
+    \vskip\z@skip
+  \else
+    \@bsphack
+    \vadjust{\@restorepar
+      \nobreak
+      \vskip #1%
+      \vskip\z@skip
+    }%
+    \@esphack
+  \fi
+}}
+\@ifdefinable\@nobreakcr{\def\@nobreakcr{%
+  \@ifstar{\@normalcr*}{\@normalcr*}%
+}}
+\newcommand*\startbreaks{%
+  \interlinepenalty 200%
+  \let\par\@@par
+  \let\\\@normalcr
+  \let\vspace\@@vspace
+}
+\@ifdefinable\@par@stopbreaks{\def\@par@stopbreaks{%
+  \par\nobreak\stopbreaks
+}}
+\@ifdefinable\@@letter{\def\@@letter#1#2#3{%
+  \ifx#2N%
+    \renewcommand*\makepresentation{\makenormalpresentation}%
+    \renewenvironment*{presentation}{%
+      \normalpresentation
+    }{%
+      \endnormalpresentation
+    }%
+  \else\ifx#2F%
+    \renewcommand*\makepresentation{\makefoldedpresentation}%
+    \renewenvironment*{presentation}{%
+      \foldedpresentation
+    }{%
+      \endfoldedpresentation
+    }%
+  \fi\fi
+  \setlength\senderindentation   {\z@}%
+  \setlength\senderwidth         {#3}%
+  \setlength\addresseeindentation{#3}%
+  \setlength\addresseewidth      {\textwidth}%
+    \addtolength\addresseewidth{-\addresseeindentation}%
+  \setlength\signatureindentation{.3\textwidth}%
+  \setlength\signaturewidth      {.6\textwidth}%
+  \renewcommand*\closingindentation{\parindent}
+  \renewcommand*\signaturealignment{\centering}%
+  \standardvertspaces
+  \baseletter{}{%
+    #1%
+  }%
+}}
+\@ifdefinable\@letter{\def\@letter#1{%
+  \@@letter{\thispagestyle{#1}}%
+}}
+\newenvironment*{customletter}{%
+  \@@letter{}L%
+}{\endbaseletter}
+\newenvironment*{letter}{%
+  \@letter{firstpage}N{.5\textwidth}%
+}{\endbaseletter}
+\newenvironment*{foldedletter}{%
+  \@letter{foldedpage}F{.5\textwidth}%
+}{\endbaseletter}
+\newenvironment*{letter*}{%
+  \@letter{firstpage}N\longindentation
+}{\endbaseletter}
+\newenvironment*{foldedletter*}{%
+  \@letter{foldedpage}F\longindentation
+}{\endbaseletter}
+\newenvironment*{letterhead}{%
+  \@letter{firstletterhead}N\longindentation
+}{\endbaseletter}
+\newenvironment*{foldedletterhead}{%
+  \@letter{foldedletterhead}F\longindentation
+}{\endbaseletter}
+%    \end{macrocode}
+%
+%    \subsubsection{Addresses and subject}
+%
+%    The addresses and the subject are not composed inside inner boxes:
+%    instead, they are constructed from ``blocks'' of lines, conveniently 
+%    indented, that are contributed directly to the main vertical list.
+%    The correct indentation is achieved by a clever combination of "\parshape"
+%    and "\everypar".
+%    This unusual scheme was chosen with the intent of maintaining full control
+%    over the interline glue, but other, and simpler, ways to accomplish this
+%    are actually available (\emph{if} the interline glue is \emph{rigid}).
+%
+%    \begin{macro}{\@block@parshape}
+%    This macro, invoked at every par., is responsible for setting the
+%    indentation.
+%    \begin{macrocode}
+\@ifdefinable\@block@parshape{\def\@block@parshape{%
+  \parshape \@ne\@block@inden\@block@width
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@block@@everypar}
+%    The part of "\@block@everypar" that "\y@custom@block" uses directly.
+%    \begin{macrocode}
+\@ifdefinable\@block@@everypar{\def\@block@@everypar{%
+  \parskip\z@skip
+  \@nobreakfalse \@minipagefalse % these are already \global
+  \@new@block@false \@empty@and@false % these too
+  \everypar{\@block@parshape}%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@block@everypar}
+%    Code executed when a block or an ``"\and"-section'' begins.
+%    \changes{0.36}{2015 Feb 08}{Added a hook, \texttt{\protect\bslash
+%      @begin@block@or@and@hook}.}^^A
+%    2015 Feb~08 (v.~0.36): "\@begin@block@or@and@hook" added.
+%    \begin{macrocode}
+\@ifdefinable\@block@everypar{\def\@block@everypar{%
+  \@block@parshape
+  \@block@@everypar
+  \@begin@block@or@and@hook
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\x@custom@block}
+%    General utility macro for generating blocks that, like address blocks,
+%    haven't got a label, but for which, in exchange, the indentation and the
+%    width can be set independently of one another.  Parameters:
+%    \begin{paramlist}
+%      \param
+%        switch: \( \mbox{Y} = \mbox{add} \) space above and below,
+%        \( \mbox{N} = \mbox{don't} \) add it;\\
+%      \param
+%        block indentation from left margin (\textoken{dimen});\\
+%      \param
+%        block width (\textoken{dimen});\\
+%      \param
+%        vertical space above block (\textoken{glue});\\
+%      \param
+%        vertical space between ``"\and"-sections'' (\textoken{glue});\\
+%      \param
+%        vertical space below block (\textoken{glue});\\
+%      \param
+%        penalty for breaking before block;\\
+%      \param
+%        penalty for breaking between ``"\and"-sections'';\\
+%      \param
+%        penalty for breaking after block.
+%    \end{paramlist}
+%    \begin{macrocode}
+\@ifdefinable\x@custom@block{\def\x@custom@block#1#2#3#4#5#6#7#8#9{%
+  \@custom@block#1#4#5#6#8#9%
+  \@block@inden #2%
+  \@block@width #3%
+  \def\voidisOK{\global\let\@empty@block\@empty}%
+  \everypar{\@block@everypar}%
+  \@@custom@block #7%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\y@custom@block}
+%    General utility macro for generating blocks that, just like the block of
+%    the subject, do have a label, but for which, in exchange, both the
+%    indentation and the width are deduced from the width of the label itself.
+%    \changes{0.36}{2015 Feb 08}{Added parameter for space after label.}^^A
+%    2015 Feb~08 (v.~0.36): added new parameter for the amount of
+%    horizontal space after the label.  Parameters now are:
+%    \begin{paramlist}
+%      \param
+%        switch: \( \mbox{Y} = \mbox{add} \) space above and below,
+%        \( \mbox{N} = \mbox{don't} \) add it;\\
+%      \param
+%        label;\\
+%      \param
+%        horizontal space after label (\textoken{dimen});\\
+%      \param
+%        vertical space above block (\textoken{glue});\\
+%      \param
+%        vertical space between ``"\and"-sections'' (\textoken{glue});\\
+%      \param
+%        vertical space below block (\textoken{glue});\\
+%      \param
+%        penalty for breaking before block;\\
+%      \param
+%        penalty for breaking between ``"\and"-sections'';\\
+%      \param
+%        penalty for breaking after block.
+%    \end{paramlist}
+%    \begin{macrocode}
+\@ifdefinable\y@custom@block{\def\y@custom@block#1#2#3#4#5#6#7#8#9{%
+  \@custom@block#1#4#5#6#8#9%
+  \sbox\@labels{\normalfont\ignorespaces #2\unskip}%
+    % We use \@labels to save a box register.
+  \@block@inden\wd\@labels
+  \ifdim\@block@inden>\z@
+    \advance \@block@inden #3\relax
+    \wd\@labels\@block@inden
+  \fi
+  \@block@width\textwidth \advance\@block@width -\@block@inden
+  \everypar{%
+    \parshape \tw@ \z@\textwidth \@block@inden\@block@width
+    \box\@labels
+    \@block@@everypar
+  }%
+  \@@custom@block #7%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\@ifdefinable\@custom@block{\def\@custom@block#1#2#3#4#5#6{%
+  \if@inlabel \indent \fi
+  \let\par\@@par \par
+  \if@newlist \@noitemerr \fi
+  \let\makelabel\m@kel@bel
+  \@nobreakfalse
+  \@noskipsecfalse
+  \@totalleftmargin\z@
+  \leftskip\z@skip \rightskip\z@skip \@rightskip\z@skip
+  \parfillskip\@flushglue
+  \ifx#1Y%
+    \parskip #2\relax
+    \ifdim\lastskip>\parskip
+      \parskip\z@skip
+    \else
+      \advance\parskip -\lastskip
+    \fi
+  \else
+    \parskip\z@skip
+  \fi
+  \parindent\z@
+  \linewidth\textwidth
+  \hsize\textwidth
+  \@block@space #4%
+  \@block@andspace #3%
+  \@i@penalty #5%
+  \@e@penalty #6%
+  \stopbreaks
+  \@new@block@true \@empty@and@true
+}}
+\@ifdefinable\@@custom@block{\def\@@custom@block#1{%
+  \addpenalty #1%
+  \color@begingroup
+}}
+\def\end@custom@block#1{\par
+  \color@endgroup
+  \if@new@block@
+    \@empty@block
+  \else
+    \if@empty@and@
+      \@empty@and
+    \fi
+    \ifx#1Y%
+      \addpenalty\@e@penalty
+      \addvspace\@block@space
+    \fi
+  \fi
+  \everypar{}%
+}
+\newcommand*\makeandvspace{%
+  \addpenalty\@i@penalty
+  \addvspace\@block@andspace
+}
+\newcommand*\makeandcclabel[1][\andccname]{%
+  \makebox[\z@][r]{\normalfont\@safe@space{#1}\quad}%
+  \ignorespaces
+}
+\@ifdefinable\@block@nd{\def\@block@nd{\par
+  \if@empty@and@
+    \@empty@and
+  \else
+    \makeandvspace
+  \fi
+  \@empty@and@true
+  \everypar{\@block@everypar}%
+}}
+\@ifdefinable\@empty@and{\def\@empty@and{%
+  \ClassWarning{\@letteracdp}{%
+    \protect\and\space with nothing inside%
+  }%
+}}
+\@ifdefinable\@empty@sender{\def\@empty@sender{%
+  \ClassWarning{\@letteracdp}{%
+    Empty sender address%
+  }%
+}}
+\@ifdefinable\@sender{\def\@sender#1{%
+  \let\@empty@block\@empty@sender
+  \let\and\@block@nd
+  \x@custom@block #1%
+    \senderindentation\senderwidth
+    \aboveaddressvspace\andaddressvspace\belowaddressvspace
+    \@b@frompenalty\@i@frompenalty\@e@frompenalty
+  \raggedright
+}}
+\newenvironment*{sender} {\@sender Y}{\end@custom@block Y}
+\newenvironment*{sender*}{\@sender N}{\end@custom@block N}
+\@ifdefinable\@empty@addressee{\def\@empty@addressee{%
+  \ClassWarning{\@letteracdp}{%
+    Empty addressee address%
+  }%
+}}
+\@ifdefinable\@addressee{\def\@addressee#1{%
+  \let\@empty@block\@empty@addressee
+  \let\and\@block@nd
+  \def\andcc{\@block@nd
+    \everypar\expandafter{\the\everypar
+      \makeandcclabel\relax
+    }%
+  }%
+  \x@custom@block #1%
+    \addresseeindentation\addresseewidth
+    \aboveaddressvspace\andaddressvspace\belowaddressvspace
+    \@b@topenalty\@i@topenalty\@e@topenalty
+  \raggedright
+}}
+\newenvironment*{addressee} {\@addressee Y}{\end@custom@block Y}
+\newenvironment*{addressee*}{\@addressee N}{\end@custom@block N}
+\@ifdefinable\@good@prsbj{\def\@good@prsbj#1{%
+  \@new@block@false \@empty@and@false
+  \let\presubject\@bad@prsbj
+  \vskip\parskip
+  \leftline{\normalfont\ignorespaces #1\unskip}%
+  \nobreak
+  \parskip\presubjectvspace
+}}
+\@ifdefinable\@bad@prsbj{\def\@bad@prsbj#1{%
+  \ClassError{\@letteracdp}{%
+    Misused \protect\presubject%
+  }{%
+    At the beginning of the subject of a letter
+    you can write something like\MessageBreak
+    \protect\presubject{A short phrase...}
+    in order to typeset "A short phrase..."\MessageBreak
+    just above the subject; but the \protect\presubject\space
+    command must come before\MessageBreak
+    any other text in the subject,
+    and it cannot be used twice.\MessageBreak
+    (If you are wondering where you used the
+    \protect\presubject\space command,\MessageBreak
+    recall that both \protect\registered\space and
+    \protect\registeredRR\space invoke
+    \protect\presubject.)\MessageBreak
+    The offending command will be ignored:
+    try to type \space <return> \space to proceed.%
+  }%
+}}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@subject}
+%    Inner implementation of \env{subject}\slash\env{subject*} environments.
+%    \changes{0.36}{2015 Feb 08}{Now this macro passes
+%      \texttt{\protect\bslash subjectnamegap} as parameter~\#3 to
+%      \texttt{\protect\bslash y@custom@block}.}^^A
+%    2015 Feb~08 (v.~0.36): now passes the "\subjectnamegap" macro
+%    as parameter~\#3 to "\y@custom@block", parameter added in this same
+%    version.
+%    \begin{macrocode}
+\@ifdefinable\@subject{\def\@subject#1#2{%
+  \let\@empty@block\@empty
+  \y@custom@block #1%
+    {#2}\subjectnamegap
+    \abovesubjectvspace\z@skip\belowsubjectvspace
+    \@b@subjpenalty\@M\@e@subjpenalty
+  \let\presubject\@good@prsbj
+  \def\registered  {\presubject{\registeredname}}%
+  \def\registeredRR{\presubject{\registeredRRname}}%
+  \everypar\expandafter{\the\everypar
+    \let\presubject\@bad@prsbj
+  }%
+  \@subject@style
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\newenvironment*{subject} [1][\subjectname]
+  {\@subject Y{#1}}{\end@custom@block Y}
+\newenvironment*{subject*}[1][\subjectname]
+  {\@subject N{#1}}{\end@custom@block N}
+\newcommand*\ifemptyblock{%
+  \if@new@block@
+    \expandafter\@firstoftwo
+  \else
+    \expandafter\@secondoftwo
+  \fi
+}
+\@ifdefinable\@makesender{\def\@makesender#1{%
+  \begin{sender#1}\thesenderaddress\end{sender#1}%
+}}
+\newcommand*\makesender{%
+  \@ifstar{\@makesender *}{\@makesender {}}%
+}
+\@ifdefinable\@makeaddressee{\def\@makeaddressee#1{%
+  \begin{addressee#1}\theaddresseeaddress\end{addressee#1}%
+}}
+\newcommand*\makeaddressee{%
+  \@ifstar{\@makeaddressee *}{\@makeaddressee {}}%
+}
+\newcommand*\x@makesubject[1][\subjectname]{%
+  \begin{subject}[#1]\thesubject\end{subject}%
+}
+\newcommand*\y@makesubject[1][\subjectname]{%
+  \begin{subject*}[#1]\thesubject\end{subject*}%
+}
+\newcommand*\makesubject{\@ifstar\y@makesubject\x@makesubject}
+%    \end{macrocode}
+%
+%    \subsubsection{Presentations}
+%
+%    With this funny term we denote the initial part of a letter
+%    (addresses and the like).
+%
+%    \begin{macro}{\@setup@pres}
+%    Code for setting up style parameters.
+%    \begin{macrocode}
+\@ifdefinable\@setup@pres{\def\@setup@pres{%
+  \global\@topnum\z@ % prevents figures from going at top of page
+  \parskip\z@skip
+  \parindent\z@
+  \@b@frompenalty \@M
+  \@i@frompenalty \@fold@toppenalty
+  \@e@frompenalty \@M
+  \@b@topenalty   \@fold@toppenalty
+  \@i@topenalty   \@fold@toppenalty
+  \@e@topenalty   \@M
+  \@b@subjpenalty \@fold@toppenalty
+  \@e@subjpenalty \@M
+  \interlinepenalty\@M
+  \def\par{\ifvmode\else\@@par\penalty\@fold@toppenalty\fi}%
+  \let\\\@nobreakcr
+  \let\vspace\@nobreakvspace
+}}
+\newenvironment*{presentation}{%
+  \normalpresentation
+}{%
+  \endnormalpresentation
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{environment}{normalpresentation}
+%    The environment for making a normal presentation:
+%    \begin{macrocode}
+\newenvironment*{normalpresentation}{%
+  \cleardoublepage
+  \@setup@pres
+}{%
+%    \end{macrocode}
+%    \changes{0.34}{2006 Jan 01}{At the end of the environment, changed
+%      \texttt{\protect\bslash par} into \texttt{\protect\bslash @@par}.}^^A
+%    Changed the following line from "\par" to "\@@par" (v.~0.34):
+%    \begin{macrocode}
+  \@@par
+  \addpenalty\@e@prespenalty
+  \addvspace\belowpresentationvspace
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    \begin{macro}{\@nofoldwarning}
+%    Warning issued when folded presentations are not allowed:
+%    \begin{macrocode}
+\@ifdefinable\@nofoldwarning{\def\@nofoldwarning{%
+  \ClassWarning{\@letteracdp}{%
+    The paper format you chose does not allow\MessageBreak
+    folded letters; making normal presentation.\MessageBreak
+    (Modify \protect\foldedheight\space in the preamble\MessageBreak
+    if you want to alter the default behavior.)\MessageBreak
+    Warning issued%
+  }%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{environment}{foldedpresentation}
+%    The environment for making a folded presentation, possibly
+%    splitting it into two parts: the part the actually fits in the folded
+%    flap, and the other, which is merged with the text below the
+%    folding.  I~think it's better to include some comments here.
+%    \begin{macrocode}
+\newenvironment*{foldedpresentation}{%
+%    \end{macrocode}
+%    Are folded letters currently allowed?
+%    \begin{macrocode}
+  \if@do@fold@
+%    \end{macrocode}
+%    \emph{Yes.} First, ensure that we are at the beginning of a page;
+%    note that \emph{numbered} pages, here, are inserted if there is a gap
+%    to be filled.
+%    \begin{macrocode}
+    \cleardoublepage
+%    \end{macrocode}
+%    The contents of the presentation will be saved in "\box0": set up
+%    parameters, color support\ldots
+%    \begin{macrocode}
+    \setbox\z@\vbox\bgroup
+      \@setup@pres
+%    \end{macrocode}
+%    \changes{0.34}{2006 Jan 01}{Added setting of
+%      \texttt{\protect\bslash boxmaxdepth} at the beginning of the 
+%      environment.}^^A
+%    Added the following line (v.~0.34), even if the depth of "\box0" 
+%    will be checked later:
+%    \begin{macrocode}
+      \boxmaxdepth\maxdepth
+%    \end{macrocode}
+%    \ldots color support, we were saying\ldots
+%    \begin{macrocode}
+      \color@begingroup
+%    \end{macrocode}
+%    The reason for this "\penalty" will be explained later~($*$):
+%    \begin{macrocode}
+      \penalty-\@M
+%    \end{macrocode}
+%    \changes{0.34}{2006 Jan 01}{Removed a superfluous setting of
+%      \texttt{\protect\bslash prevdepth} from the beginning of the 
+%      environment.}^^A
+%    Removed the following line (v.~0.34): we have no need to insert
+%    interline glue here, and it is even wrong to do it; we will insert the
+%    "\topskip" glue below with a trick (which, in any case, would remove
+%    the---incorrect---interline glue inserted here).  Why did I include
+%    this redundant statement?
+%\begin{verbatim}
+%\prevdepth\z@
+%\end{verbatim}
+%    \begin{macrocode}
+  \else
+%    \end{macrocode}
+%    \emph{No.} Inform the user and substitute a normal presentation.
+%    \begin{macrocode}
+    \@nofoldwarning
+    \normalpresentation
+  \fi
+}{%
+%    \end{macrocode}
+%
+%    When the presentation ends, if we were making a folded
+%    presentation\ldots
+%    \begin{macrocode}
+  \if@do@fold@
+%    \end{macrocode}
+%    \ldots finish off the box\ldots
+%    \begin{macrocode}
+      \@@par
+      \color@endgroup
+%    \end{macrocode}
+%    \ldots and save its "\prevdepth" for later.
+%    \begin{macrocode}
+      \global\dimen@i\prevdepth
+%    \end{macrocode}
+%    Insert the equivalent of "\foldingfilbreak[0]": if possible, the
+%    "\vsplit" that will later split the presentation should try to split
+%    it here (\emph{i.e.}, not to split it at all).
+%    \begin{macrocode}
+      \@f@ldingfilbreak\@fold@basepenalty
+%    \end{macrocode}
+%    But "\vsplit" might prefer to split the box at the implicit
+%    "\penalty-10000" inserted at its end; avoid this, since it would
+%    defeat the "\vfil" of "\@f@ldingfilbreak":\nobreak\space($**$)
+%    \begin{macrocode}
+      \vskip\maxdimen % "discourage" the break at the \penalty-10000
+%    \end{macrocode}
+%    End of "\vbox".
+%    \begin{macrocode}
+    \egroup
+%    \end{macrocode}
+%    Now "\box0" contains the presentation, but it lacks the due
+%    "\topskip" glue atop.  Of course, we could have inserted the
+%    equivalent (in normal circumstances) of the "\topskip" glue by
+%    setting \[ "\prevdepth" := "\topskip"-"\baselineskip" \] at the
+%    beginning of "\box0", but this does not work always, since it could
+%    insert the "\lineskip" glue instead.  We are admittedly whimsical
+%    here, but, in order to achieve exactly the same result yielded by
+%    the "\topskip" glue machinery operated in the main vertical list, we
+%    use the following trick of "\vsplit"'ting "\box0" to \texttt{0pt}.
+%    A legal breakpoint exists for this: it is the "\penalty-10000"
+%    inserted above in~($*$)!  This breakpoint comes first in "\box0" and
+%    it is mandatory, so the "\vsplit" operation will stop immediately
+%    (without consuming time); nothing will be actually split off,
+%    everything will remain in "\box0", but with "\splittopskip" glue
+%    added at the top!  Moreover, although we set "\boxmaxdepth" inside
+%    "\box0", we check again for possible excess depth (can't figure out
+%    how it could creep in, however).  So:
+%    \begin{macrocode}
+    \splitmaxdepth\maxdepth
+    \splittopskip\topskip
+    \setbox\tw@\vsplit\z@ to\z@
+%    \end{macrocode}
+%    The real splitting of the presentation is done by the following
+%    "\vsplit": the baseline of the first line possibly remaining in
+%    "\box0" after the "\vsplit" must be at a distance of
+%    "\@below@folding@skip" from the folding, plus the "\parskip" glue
+%    and, of course, the normal interline glue (we are in mid-page now).
+%    \begin{macrocode}
+    \splittopskip\baselineskip
+    \advance\splittopskip\@below@folding@skip
+    \advance\splittopskip\parskip
+    \setbox\tw@\vsplit\z@ to\@folding@ht
+%    \end{macrocode}
+%    Now "\box2" contains the part of the presentation that does fit in the
+%    folded flap; we append this box to the page (actually, it is the first
+%    thing contributed since the "\cleardoublepage").  Since this box already
+%    includes "\topskip" glue at the top, we take redundant precautions to
+%    ensure that no such glue is added again here.
+%    \begin{macrocode}
+    {\topskip\z@skip \box\tw@
+%    \end{macrocode}
+%    Thanks to the above setting of "\splitmaxdepth", we are sure that
+%    the depth of the previous box is small; so the following line will
+%    take us exactly on the edge of the fold, with null depth\ldots
+%    \begin{macrocode}
+    \baselineskip\@above@folding@margin \nobreak\null}%
+%    \end{macrocode}
+%    \ldots where we insert a costly, yet feasible breakpoint.
+%    \begin{macrocode}
+    \penalty\@highpenalty
+%    \end{macrocode}
+%    If everything fitted in the folded flap, nothing remained in
+%    "\box0".
+%    \begin{macrocode}
+    \ifvoid\z@
+%    \end{macrocode}
+%    In that case, just leave appropriate blank space (the "\prevdepth"
+%    is already zero, so the interline glue of the following line will be
+%    correct).
+%    \begin{macrocode}
+      \vskip\@below@folding@skip
+%    \end{macrocode}
+%    Otherwise, take the part that did not fit out of "\box0"\ldots
+%    \begin{macrocode}
+    \else
+      \unvbox\z@
+%    \end{macrocode}
+%    \ldots so it is now in the list of ``recent contributions''
+%    ("\unvbox" does not exercise the page builder); remove the
+%    "\vskip\maxdimen" added in~($**$) just to fool "\vsplit", as well as
+%    the items added by the virtual "\foldingfilbreak[0]".
+%    \begin{macrocode}
+      \unskip    % remove "\vskip\maxdimen"
+      \unpenalty % remove "\penalty\@fold@basepenalty"
+      \unskip    % remove "\vskip \dimen@ plus 1fil minus ..."
+      \unskip    % remove "\vskip -\skip@"
+      \unpenalty % remove "\penalty 10000"
+%    \end{macrocode}
+%    Now the list of ``recent contributions'' contains exactly what the
+%    user put in the presentation (and did not fit in the folded flap).
+%    Restore "\prevdepth" and conclude as if it were a normal
+%    presentation: this makes a perfectly seamless join with the
+%    following material, as if the folded presentation had been a normal
+%    one, extending down to this spot in the page.  ^^A ( paren match
+%    Not bad, uhu?~:-)
+%    \begin{macrocode}
+      \prevdepth\dimen@i
+      \addpenalty\@e@prespenalty
+      \addvspace\belowpresentationvspace
+%    \end{macrocode}
+%    Ah, yes, also inform the user of what happened:
+%    \begin{macrocode}
+      \ClassWarning{\@letteracdp}{%
+        Some text that did not fit into the folded flap\MessageBreak
+        was moved into the main text below the folding;\MessageBreak
+        warning issued%
+      }%
+    \fi
+%    \end{macrocode}
+%    If we were not making a folded presentation, then conclude a
+%    normal one.
+%    \begin{macrocode}
+  \else
+    \endnormalpresentation
+  \fi
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    Back to uncommented code.
+%    \begin{macrocode}
+\newcommand*\iffoldedallowed{%
+  \if@do@fold@
+    \expandafter\@firstoftwo
+  \else
+    \expandafter\@secondoftwo
+  \fi
+}
+\newcommand*\makepresentation{\makenormalpresentation}
+\newcommand*\makenormalpresentation{%
+  \begin{normalpresentation}%
+    \makesender\relax
+    \makeaddressee\relax
+    \makesubject\relax
+  \end{normalpresentation}%
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@f@ldingfilbreak}
+%    The ``upper half'' of "\@foldingfilbreak".
+%    \begin{macrocode}
+\@ifdefinable\@f@ldingfilbreak{\def\@f@ldingfilbreak#1{%
+  \ifdim\prevdepth<\maxdepth
+    \dimen@ -\prevdepth
+  \else
+    \dimen@ -\maxdepth
+  \fi
+  \skip@ \lastskip
+  \nobreak
+  \vskip -\skip@
+  \vskip \dimen@ \@plus 1fil\@minus \@above@folding@shrink
+  \penalty #1%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macrocode}
+\@ifdefinable\@foldingfilbreak{\def\@foldingfilbreak#1#2{\par
+  \@f@ldingfilbreak#1%
+  \vskip -\dimen@ \@plus -1fil\@minus -\@above@folding@shrink
+  \vskip \skip@
+  \addvspace{#2}%
+}}
+\@ifdefinable\@fold@getpen{\def\@fold@getpen#1{%
+  \ifcase #1 \@fold@basepenalty \or \@fold@lowpenalty
+    \or \@fold@medpenalty \or \@fold@highpenalty
+    \else \@fold@toppenalty \fi
+}}
+\newcommand*\foldingbreak[1][\z@]{%
+  \ifvmode
+    \penalty\@fold@getpen{#1}%
+  \else
+    \@bsphack
+    \vadjust{\penalty\@fold@getpen{#1}}%
+    \@esphack
+  \fi
+}
+\newcommand*\foldingfilbreak[1][\z@]{%
+  \@foldingfilbreak{\@fold@getpen{#1}}%
+}
+\newcommand*\makefoldedpresentation{%
+  \if@do@fold@
+    \begin{foldedpresentation}%
+      \renewcommand*\makeandvspace{%
+        \@foldingfilbreak\@fold@medpenalty\andaddressvspace
+      }%
+      \makesender\relax
+      \@foldingfilbreak\@fold@medpenalty\z@skip
+      \if@new@block@
+        \aboveaddressvspace \z@\@plus1fil\relax
+        \nointerlineskip\null\nobreak
+      \fi
+      \makeaddressee\relax
+      \@foldingfilbreak\@fold@lowpenalty\z@skip
+      \makesubject\relax
+    \end{foldedpresentation}%
+  \else
+    \@nofoldwarning
+    \makenormalpresentation
+  \fi
+}
+%    \end{macrocode}
+%
+%    \subsubsection{Date, salutation, signature, enclosures\ldots}
+%
+%    This section should be reorganized, with commands listed in a more 
+%    logical order: at present, they are rather mixed up.
+%
+%    First comes the date.
+%    \begin{macrocode}
+\@ifdefinable\@make@date{\def\@make@date#1#2#3{\par
+  \ifx#2Y%
+    \nobreak\medskip
+  \fi
+  \noindent\@safe@space{#1}\space\@date\par
+  \ifx#3Y%
+    \nobreak\medskip
+  \fi
+}}
+\newcommand*\makedate      [1][\@place]{\@make@date{#1}NN}
+\newcommand*\maketopdate   [1][\@place]{\@make@date{#1}NY}
+\newcommand*\makebottomdate[1][\@place]{\@make@date{#1}YN}
+\@ifdefinable\@empty@signature{\def\@empty@signature{%
+  \ClassWarning{\@letteracdp}{%
+    Empty signature%
+  }%
+}}
+%    \end{macrocode}
+%
+%    Then, heaven knows why, the signature.
+%
+%    \begin{macro}{\@signatureenv}
+%    Inner implementation of the \env{signatureenv}\slash\env{signatureenv*}
+%    environments.
+%    \changes{0.36}{2015 Feb 08}{Added support for \protect\opz{signaturerule}
+%      option.}^^A
+%    Added support for the \opz{signaturerule} option (vers.~0.36), exploiting
+%    the new ``hook'' "\@begin@block@or@and@hook", the gets executed whenever a
+%    signature is typeset.
+%    \begin{macrocode}
+\@ifdefinable\@signatureenv{\def\@signatureenv#1{\par
+  \let\@empty@block\@empty@signature
+  \let\and\@block@nd
+  \if@signature@rule@
+    \let \@begin@block@or@and@hook \@make@signature@rule
+  \fi
+  \x@custom@block Y%
+    \signatureindentation\signaturewidth
+    #1#1\z@skip
+    \@M\@M\@M
+  \signaturealignment\@signature@style
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\end@signatureenv}
+%    Ends a \env{signatureenv}\slash\env{signatureenv*} environment.
+%    \begin{macrocode}
+\def\end@signatureenv{%
+  \end@custom@block N% not "Y" for efficiency
+%    \end{macrocode}
+%    The following line (also added, of course, in vers.~0.36) is not actually necessary ("\@begin@block@or@and@hook"
+%    has been set by "\@signatureenv" inside a group), but redundancy does not
+%    hurt.
+%    \begin{macrocode}
+  \let \@begin@block@or@and@hook \@empty
+  \addvspace\belowsignaturevspace
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{environment}{signatureenv}
+%    For signatures that include vertical space for handwriting.
+%    \begin{macrocode}
+\newenvironment*{signatureenv}{%
+  \@signatureenv\abovesignaturevspace
+}{%
+  \end@signatureenv
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    \begin{environment}{signatureenv*}
+%    For signatures that do \emph{not} include vertical space for handwriting; 
+%    these should \emph{never} display a rule, and for this reason\ldots
+%    \begin{macrocode}
+\newenvironment*{signatureenv*}{%
+%    \end{macrocode}
+%    \changes{0.36}{2015 Feb 08}{Taken care of always suppressing rules
+%      here.}^^A
+%    \ldots~we add the following line in vers.~0.36 (note that we are inside a
+%    group).
+%    \begin{macrocode}
+  \@signature@rule@false
+  \@signatureenv\abovesignatureshortvspace
+}{%
+  \end@signatureenv
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\@ifdefinable\x@msignature{\def\x@msignature#1{%
+  \begin{signatureenv#1}%
+    \ifx\thesendersignature\@empty
+      \thesendername
+    \else
+      \thesendersignature
+    \fi
+  \end{signatureenv#1}%
+}}
+\@ifdefinable\y@msignature{\def\y@msignature{%
+  \begin{signatureenv}%
+    \vskip\parskip \vskip\z@skip
+    \the\everypar
+  \end{signatureenv}%
+}}
+\newcommand*\makesignature{\@par@stopbreaks
+  \@ifstar{%
+    \x@msignature *%
+  }{%
+    \@ifnextchar -{%
+      \@firstoftwo\y@msignature
+    }{%
+      \x@msignature {}%
+    }%
+  }%
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\@make@signature@rule}
+%    Generate a fake, raised line, containing the rule.  Added in vers.~0.36.
+%    \begin{macrocode}
+\@ifdefinable\@make@signature@rule{\def\@make@signature@rule{%
+  \raisebox{\baselineskip}[0pt][0pt]{%
+    \signaturerule
+  }\\*[-\baselineskip]%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\signaturerule}
+%    User command to allow customization of the signature rule.
+%    Added in vers.~0.36.
+%    \begin{macrocode}
+\newcommand*\signaturerule{%
+  \makebox[\signaturerulewidth]{%
+    \leaders \hrule \@height .1\p@ \@depth .1\p@ \hfill
+  }%
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Now it is the turn of the salutation (I~said the order isn't logical!).
+%
+%    \begin{macro}{\makeopening}
+%    This command generates the sheer salutation.  It comes in two flavors:
+%    \begin{description}
+%      \item[normal form:]
+%        "\makeopening{"\meta{text}"}"\\*
+%          typeset the \meta{text} as the salutation;
+%      \item[$+$-form:]
+%        "\makeopening+"\\*
+%          leave space for a handwritten salutation.
+%    \end{description}
+%    \begin{macrocode}
+\newcommand*\makeopening{\par
+  \@ifnextchar +{\@firstoftwo\y@mopening}\x@mopening
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\@ifdefinable\x@mopening{\def\x@mopening#1{%
+  \ifx\@indent@pref O%
+    \dimen@\prevdepth
+    \setbox\z@\vbox{\color@begingroup
+      \null
+      \prevdepth\dimen@
+      \noindent\null\ignorespaces #1\par
+      \global\dimen@i\prevdepth
+    \color@endgroup}%
+    \setbox\tw@\vbox{%
+      \unvcopy\z@
+      \setbox\z@\lastbox
+      \global\setbox\@ne\hbox{\unhbox\z@}%
+    }%
+    \ifdim\wd\@ne<2pc
+      \parindent 2pc\relax
+    \else\ifdim\wd\@ne>.4\textwidth
+      \parindent .1\textwidth\relax
+    \else
+      \parindent \wd\@ne
+    \fi\fi
+    \unvbox\z@
+    \prevdepth\dimen@i
+  \else
+    \noindent\null\ignorespaces #1\par
+  \fi
+  \nobreak
+}}
+\@ifdefinable\y@mopening{\def\y@mopening{%
+  \@handwr@box\z@ \nobreak
+}}
+%    \end{macrocode}
+%
+%    \begin{macro}{\opening}
+%    Well-known command for opening a letter.  In vers.~0.35, it,
+%    and related macros, have been completely reimplemented to support the
+%    "\OpeningSequence" feature.
+%    \begin{macrocode}
+\newcommand*\opening{\par
+  \@ifnextchar +{\@firstoftwo\y@opening}\x@opening
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\y@opening}
+%    Implements the ``\mbox{$+$-form}'' of the "\opening" command (salutation
+%    written by hand): "\ChosenMakeOpening" should expand to ``"\y@mopening"''.
+%    \begin{macrocode}
+\newcommand*\y@opening[1][\@place]{%
+  \@opening \y@mopening {#1}%
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\x@opening}
+%    Implements the normal form of the "\opening" command (with typeset
+%    salutation): "\ChosenMakeOpening" should expand to
+%    ``"\x@mopening{"\meta{contents of~\#2}"}"''.
+%    \begin{macrocode}
+\newcommand*\x@opening[2][\@place]{%
+  \@opening{\x@mopening{#2}}{#1}%
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@opening}
+%    Prepare call to "\OpeningSequence", then call it.  Parameters:
+%    \begin{paramlist}
+%      \param
+%        intended meaning of "\ChosenMakeOpening";\\
+%      \param
+%        contents of optional argument of "\opening" (defaults to "\@place").
+%    \end{paramlist}
+%    \begin{macrocode}
+\@ifdefinable\@opening{\def\@opening#1#2{%
+%    \end{macrocode}
+%    Keep definition of "\ChosenMakeOpening" local.
+%    \begin{macrocode}
+  \begingroup
+    \def\ChosenMakeOpening{#1}%
+%    \end{macrocode}
+%    Invoke user-customizable opening sequence.
+%    \begin{macrocode}
+    \OpeningSequence{#2}%
+%    \end{macrocode}
+%    If the \opz{smartindent} option is in force, "\parindent" might have just
+%    been changed: this change must be ``lifted'' out of the group.
+%    \begin{macrocode}
+    \global\dimen@i\parindent
+  \endgroup
+  \parindent\dimen@i
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\OpeningSequence}
+%    This command defines the ``opening sequence'', that is, the sequence of
+%    commands that should be executed when the user-level "\opening" command
+%    is given.  Provided in vers.~0.35 to allow customization.  The optional
+%    argument of "\opening" is passed in the---mandatory!---argument of this
+%    command; the mandatory argument of "\opening", if present (\emph{i.e.},
+%    if not ``\mbox{$+$-form}'') is embodied in "\ChosenMakeOpening".
+%    Factory definition:
+%    \begin{macrocode}
+\newcommand*\OpeningSequence[1]{%
+  \makepresentation
+  \maketopdate[#1]%
+  \ChosenMakeOpening
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    A little bit of uncommented code.
+%    \begin{macrocode}
+\newcommand*\makeclosing{\@par@stopbreaks
+  \@ifnextchar +{\@firstoftwo\y@mclosing}\x@mclosing
+}
+\@ifdefinable\x@mclosing{\def\x@mclosing#1{%
+  \noindent\hspace*{\closingindentation}\ignorespaces #1\par
+}}
+\@ifdefinable\y@mclosing{\def\y@mclosing{%
+  \@handwr@box\closingindentation
+}}
+%    \end{macrocode}
+%
+%    \begin{macro}{\closing}
+%    Well-known command for closing a letter.  In vers.~0.35, it,
+%    and related macros, have been completely reimplemented to support the
+%    "\ClosingSequence" feature.  The present implementation support exactly
+%    the same modifiers as the former one (cf.~\cite{nts}), \emph{i.e.}:
+%    \begin{description}
+%      \item[normal form:]
+%        "\closing{"\meta{text}"}"\\*
+%          typeset the \meta{text} as the closing sentence,
+%          using the internal equivalent of "\makeclosing{"\meta{text}"}";
+%          an ordinary signature (the internal equivalent of "\makesignature")
+%          follows;
+%      \item[$*$-form:]
+%        "\closing*{"\meta{text}"}"\\*
+%          typeset the \meta{text} as the closing sentence,
+%          using the internal equivalent of "\makeclosing{"\meta{text}"}";
+%          a compressed signature (the internal equivalent of
+%          "\makesignature*") follows;
+%      \item[$+$-form:]
+%        "\closing+"\\*
+%          leave space for a handwritten closing sentence (as "\makeclosing+"
+%          would do),
+%          followed by another space for an equally handwritten signature
+%          (like the one produced by "\makesignature-");
+%      \item[$-$-form:]
+%        "\closing-{"\meta{text}"}"\\*
+%          typeset the \meta{text} as the closing sentence,
+%          using the internal equivalent of "\makeclosing{"\meta{text}"}",
+%          followed by the space for a handwritten signature
+%          (like the one produced by "\makesignature-").
+%    \end{description}
+%    \begin{macrocode}
+\newcommand*\closing{\@par@stopbreaks
+  \@ifstar{%
+    \@closing{\x@msignature *}%
+  }{%
+    \@ifnextchar +{\@firstoftwo{%
+      \@@closing \y@mclosing \y@msignature
+    }}{%
+      \@ifnextchar -{\@firstoftwo{%
+        \@closing \y@msignature
+      }}{%
+        \@closing{\x@msignature {}}%
+      }%
+    }%
+  }%
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@closing}
+%    The sole purpose of this macro is to absorb the argument destined for the
+%    "\closing" command (which is absent in the ``\mbox{$+$-form}, though),
+%    which becomes argument~\#2; argument~\#1 is the token sequence that should
+%    be used to generate the signature.
+%    \begin{macrocode}
+\@ifdefinable\@closing{\def\@closing#1#2{%
+  \@@closing{\x@mclosing{#2}}{#1}%
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@@closing}
+%    Prepare call to "\ClosingSequence", then call it.  Parameters:
+%    \begin{paramlist}
+%      \param
+%        intended meaning of "\ChosenMakeClosing";\\
+%      \param
+%        intended meaning of "\ChosenMakeSignature".
+%    \end{paramlist}
+%    \begin{macrocode}
+\@ifdefinable\@@closing{\def\@@closing#1#2{%
+%    \end{macrocode}
+%    Keep definitions local.
+%    \begin{macrocode}
+  \begingroup
+    \def\ChosenMakeClosing{#1}%
+    \def\ChosenMakeSignature{#2}%
+%    \end{macrocode}
+%    Invoke user-customizable closing sequence.
+%    \begin{macrocode}
+    \ClosingSequence
+  \endgroup
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\ClosingSequence}
+%    This command defines the ``closing sequence'', that is, the sequence of
+%    commands that should be executed when the user-level "\closing" command
+%    is given.  Provided in vers.~0.35 to allow customization.
+%    Factory definition:
+%    \begin{macrocode}
+\newcommand*\ClosingSequence{%
+  \ChosenMakeClosing
+  \ChosenMakeSignature
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@handwr@box}
+%    Draws an almost imperceptible sign that marks the spot where a handwritten
+%    salutation, or closing sentence, should start.  \#1~is the amount of
+%    indentation.
+%    \begin{macrocode}
+\@ifdefinable\@handwr@box{\def\@handwr@box#1{%
+  \vskip .5\baselineskip
+  \setbox\z@\vbox{%
+    \hrule\@height .1\p@ \@depth .1\p@ \@width 3\p@
+  }%
+  \wd\z@\z@ \ht\z@\z@ \dp\z@\z@ \noindent\hspace*{#1}\box\z@\par
+  \vskip .5\baselineskip\vskip\z@skip
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macro}{\@cc@encl}
+%    Inner implementation for both "\cc" and "\encl".
+%    \changes{0.36}{2015 Feb 08}{Fully reimplemented by means of
+%      ``blocks''.}^^A
+%    Wholly rewritten in vers.~0.36, now uses ``blocks'' (like addresses and
+%    subject).  This, among other things, ensures coherent treatment of the
+%    interline glue.
+%    \begin{macrocode}
+\@ifdefinable\@cc@encl{\long\def\@cc@encl#1#2{\par
+  \begingroup
+    \let\@empty@block\@empty
+    \y@custom@block N{#1}{.5em}%
+      \z@skip\z@skip\z@skip
+      \@M\z@\z@
+    \ignorespaces #2%
+    \end@custom@block N%
+  \endgroup
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\newcommand*\cc  [1][\ccname]  {\@cc@encl{#1}}
+\newcommand*\encl[1][\enclname]{\@cc@encl{#1}}
+\newenvironment{enclosures}[1][\enclname]{%
+  \baseenclosures[#1]{}%
+}{%
+  \endbaseenclosures
+}
+\newenvironment{baseenclosures}[2][\enclname]{\par
+  \addpenalty{-\@lowpenalty}%
+  \addvspace{\bigskipamount}%
+  \startbreaks
+  \parskip\z@skip
+  {\parindent\z@ #1\par}%
+  \list{\labelenumi}{%
+    \usecounter{enumi}%
+    \@beginparpenalty\@M
+    \@itempenalty-\@lowpenalty
+    \@endparpenalty-\@medpenalty
+%% ( paren match
+    \renewcommand*\labelenumi{\theenumi)}%
+    #2%
+  }%
+}{%
+  \endlist
+  \aftergroup\startbreaks
+}
+\newcommand*\ps{\par\startbreaks\parindent\z@}
+\newcommand*\@PS@rigid [1][\PSname]{%
+  {\normalfont\@safe@space{#1}\enspace}\ignorespaces
+}
+\newcommand*\@PS@rubber[1][\PSname]{%
+  \@safe@space{#1}{\nobreak\space}\ignorespaces
+}
+\newcommand*\PS{%
+  \ps\@ifstar{\@PS@rubber}{\@PS@rigid}%
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\stopletter}
+%    User-level hook invoked (before anything else) when a letter ends.
+%    \begin{macrocode}
+\newcommand*\stopletter{}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \subsubsection{Address labels}
+%
+%    This part of the code should probably be detached and put in a 
+%    separate file to be loaded on demand.
+%
+%    The general idea is the following:
+%    \begin{itemize}
+%    \item
+%    a \env{labels} (or \env{baselabels}, see below) environment
+%    produces one or more sheets of address labels;
+%    \item
+%    inside \env{labels}, several \env{labelgroup} environments wrap up
+%    the address labels pertaining to each letter (a letter may have
+%    several address labels associated with it, if it has several
+%    addressees);
+%    \item
+%    inside each \env{labelgroup} environment, individual labels are
+%    produced with the "\basemlabel" command.
+%    \end{itemize}
+%    The \env{labels} environment takes care of such things like jumping
+%    to a new page, etc.; the \env{labelgroup} environment merely changes
+%    the way address labels are numbered, but does not otherwise affect
+%    the printout.
+%
+%    The user may either:
+%    \begin{enumerate}
+%    \renewcommand*{\theenumi}{(\Alph{enumi})}
+%    \renewcommand*{\labelenumi}{\theenumi}
+%    \item\label{autolabels}
+%    include a "\makelabels" declaration in the preamble, to have 
+%    address labels generated automatically via the \filedir{.aux} 
+%    file; in this case, appropriate commands are written in the 
+%    \filedir{.aux} file by each 
+%    \env{baseletter} environment, which, when the \filedir{.aux} file 
+%    is re-read at the "\end{document}", automatically generate the 
+%    required environments and commands (\env{labels}, 
+%    \env{labelgroup}, etc.); \emph{or}
+%    \item\label{handlabels}
+%    produce the address labels ``by hand'', including directly in the
+%    source file, where (s)he want the address label sheets to appear, a
+%    \env{labels} environment, containing the appropriate
+%    \env{labelgroup} environments, containing, in turn, the individual
+%    "\basemlabel" commands.
+%    \end{enumerate}
+%    In principle, it is also possible to mix \ref{autolabels} 
+%    and~\ref{handlabels} (and to have several \env{labels} 
+%    environments, too), but this has no practical utility.
+%
+%    \begin{macrocode}
+\newcommand*\returnaddress{\thesenderaddress}
+\@ifdefinable\@emptyaddrlabels@err{\def\@emptyaddrlabels@err{%
+  \advance \@cdp@gencount \m@ne
+  \ClassError{\@letteracdp}{%
+    Counter emptyaddrlabels out of range%
+  }{%
+    The counter emptyaddrlabels holds
+    the number of labels\MessageBreak
+    to leave blank when starting to print
+    the address labels\MessageBreak
+    (e.g., because some labels
+    have already been peeled off).\MessageBreak
+    For the label format you chose,
+    it must lie in the range\MessageBreak
+    0..\number\@cdp@gencount\space (inclusive),
+    but presently its value is \number\c@emptyaddrlabels.\MessageBreak
+    It will therefore be ignored;
+    type \space <return> \space to proceed.%
+  }%
+}}
+\newcommand*\skipemptylabels{%
+  \@cdp@gencount \c@addrlabelrows
+  \multiply \@cdp@gencount \c@addrlabelcolumns
+  \ifnum\c@emptyaddrlabels<\z@
+    \@emptyaddrlabels@err
+  \else\ifnum\c@emptyaddrlabels<\@cdp@gencount
+    \begingroup
+      \let\ifactuallabel\@secondoftwo
+      \@whilenum\c@totallabel<\c@emptyaddrlabels\do{\basemlabel{}{}}%
+    \endgroup
+  \else
+    \@emptyaddrlabels@err
+  \fi\fi
+}
+%    \end{macrocode}
+%
+%    \begin{environment}{baselabels}
+%    This is the actual environment for producing sheets of address labels: the
+%    \env{labels} environment (see below) is simply a wrapper that offers the
+%    user the chance of making some changes after calling \env{baselabels}.
+%    \changes{0.36d}{2018 Feb 08}{Added \texttt{\protect\bslash global} before 
+%      \texttt{\protect\bslash c@page\protect\bslash @ne}.}^^A
+%    V.~0.36d: "\global\c@page\@ne".
+%    \begin{macrocode}
+\newenvironment*{baselabels}{%
+  \cleardoubleemptypage
+  \global\c@page\@ne
+  \typeout{Address Labels}%
+  \pagestyle{empty}%
+  \textwidth \c@addrlabelcolumns\addrlabelwidth
+  \count@ \c@addrlabelcolumns
+  \advance \count@ \m@ne
+  \ifnum\count@>\z@
+    \advance \textwidth \count@\addrlabelshsep
+  \fi
+  \linewidth\textwidth \hsize\textwidth
+  \oddsidemargin -1in%
+  \advance \oddsidemargin \addrlabelsleftmargin
+  \evensidemargin \oddsidemargin
+  \@totalleftmargin\z@
+  \leftskip\z@skip \rightskip\z@skip \@rightskip\z@skip
+  \parfillskip\@flushglue
+  \textheight \c@addrlabelrows\addrlabelheight
+  \count@ \c@addrlabelrows
+  \advance \count@ \m@ne
+  \ifnum\count@>\z@
+    \advance \textheight \count@\addrlabelsvsep
+  \fi
+  \@colht\textheight  \@colroom\textheight \vsize\textheight
+  \headsep \z@
+  \headheight \z@
+  \footskip \z@
+  \topmargin -1in%
+  \advance \topmargin \addrlabelstopmargin
+  \ifcase \@ptsize\relax
+    \normalsize
+  \or
+    \small
+  \or
+    \footnotesize
+  \fi
+  \parindent \z@
+  \baselineskip \z@skip
+  \lineskip \z@skip
+  \boxmaxdepth \z@
+  \raggedright
+  \fboxrule \z@
+  \fboxsep \addrlabelborder
+  \addrlabeltrimwidth \addrlabelwidth
+  \advance \addrlabeltrimwidth -2\addrlabelborder
+  \addrlabeltrimheight \addrlabelheight
+  \advance \addrlabeltrimheight -2\addrlabelborder
+  \setcounter{totallabel}{\z@}%
+  \setcounter{label}{\z@}%
+  \setcounter{letter}{\z@}%
+  \noindent
+  \skipemptylabels
+}{%
+  \@killglue\clearpage
+}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    \begin{environment}{labels}
+%    It is the user-level environment for producing one or more sheets of 
+%    address labels. 
+%    Its default definition simply invokes \env{baselables}, but the 
+%    user may redefine it to set some style parameters.  For example:
+%\begin{verbatim}
+%\renewenvironment{labels}{%
+%    \baselabels
+%    \setlength\fboxrule{.2pt}%
+%    \addtolength\fboxsep{-2\fboxrule}%
+%}{\endbaselabels}
+%\end{verbatim}
+%    will draw a thin border around each address label.
+%    \begin{macrocode}
+\newenvironment*{labels}{\baselabels}{\endbaselabels}
+%    \end{macrocode}
+%    \end{environment}
+%
+%    Back to uncommented code.
+%    \begin{macrocode}
+\let\@beginlabels=\relax
+\let\@endlabels=\relax
+\newenvironment*{labelgroup}{\stepcounter{letter}}{}
+\let\@beginlabelgroup=\relax
+\let\@endlabelgroup=\relax
+\newcommand*\labeltab{\@killglue
+  \ifnum\c@totallabel>\z@
+    \count@ \c@totallabel
+    \divide \count@ \c@addrlabelcolumns
+    \multiply \count@ -\c@addrlabelcolumns
+    \advance \count@ \c@totallabel
+    \ifnum\count@=\z@
+      \par\vskip\addrlabelsvsep\noindent
+    \else
+      \hskip\addrlabelshsep
+    \fi
+  \fi
+  \stepcounter{totallabel}%
+  \stepcounter{label}%
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\ifactuallabel}
+%    Macro for the user: "\ifactuallabel{"\meta{FOO}"}{"\meta{BAR}"}"
+%    executes \meta{FOO} if the label is not being skipped, \meta{BAR}
+%    otherwise.
+%    \begin{macrocode}
+\let\ifactuallabel\@firstoftwo
+%    \end{macrocode}
+%    \end{macro}
+%
+%    \begin{macrocode}
+\newcommand\basemlabel[2]{%
+  \begingroup
+    \def\startaddrlabel{\par
+      \noindent \vrule\@height\topskip \@depth\z@ \@width\z@ \par
+      \vskip-\baselineskip \vskip\z@skip
+    }%
+    \def\stopaddrlabel{\par
+      \ifnum\prevdepth>\z@
+        \kern -\prevdepth
+        \prevdepth\z@
+      \fi
+    }%
+    \labeltab\mlabel{\ignorespaces #1}{\ignorespaces #2}%
+  \endgroup
+}
+\newcommand\mlabel[2]{%
+  \fbox{%
+    \parbox[c][\addrlabeltrimheight]{\addrlabeltrimwidth}{%
+      \raggedright\startaddrlabel #2\stopaddrlabel
+    }%
+  }%
+}
+\let\@mlabel=\@gobbletwo
+%    \end{macrocode}
+%
+%    \subsubsection{Lists and other similar environments}
+%
+%    \begin{macrocode}
+\normalfont \normalsize
+\setlength\leftmargini  {2em}
+\setlength\leftmarginii {2em}
+\setlength\leftmarginiii{2em}
+\setlength\leftmarginiv {1.75em}
+\setlength\leftmarginv  {1.5em}
+\setlength\leftmarginvi {1.5em}
+\setlength\leftmargin   {\leftmargini}
+\setlength  \labelsep  {.5em}
+\setlength  \labelwidth{\leftmargini}
+\addtolength\labelwidth{-\labelsep}
+\setlength\partopsep{\z@skip}
+\@beginparpenalty -\@lowpenalty
+\@endparpenalty   -\@lowpenalty
+\@itempenalty     -\@lowpenalty
+\def\@listI{\leftmargin\leftmargini
+            \parsep \smallskipamount
+            \topsep \medskipamount
+            \itemsep\smallskipamount}
+\let\@listi\@listI
+\@listi
+\def\@listii {\leftmargin\leftmarginii
+              \labelwidth\leftmarginii
+              \advance\labelwidth-\labelsep
+              \topsep\smallskipamount
+              \parsep\z@skip}
+\def\@listiii{\leftmargin\leftmarginiii
+              \labelwidth\leftmarginiii
+              \advance\labelwidth-\labelsep}
+\def\@listiv {\leftmargin\leftmarginiv
+              \labelwidth\leftmarginiv
+              \advance\labelwidth-\labelsep}
+\def\@listv  {\leftmargin\leftmarginv
+              \labelwidth\leftmarginv
+              \advance\labelwidth-\labelsep}
+\def\@listvi {\leftmargin\leftmarginvi
+              \labelwidth\leftmarginvi
+              \advance\labelwidth-\labelsep}
+\renewcommand*\theenumi{\@arabic\c@enumi}
+\renewcommand*\theenumii{\@alph\c@enumii}
+\renewcommand*\theenumiii{\@roman\c@enumiii}
+\renewcommand*\theenumiv{\@Alph\c@enumiv}
+\newcommand*\labelenumi{\theenumi.}
+\newcommand*\labelenumii{(\theenumii)}
+\newcommand*\labelenumiii{\theenumiii.}
+\newcommand*\labelenumiv{\theenumiv.}
+\renewcommand*\p@enumii{\theenumi}
+\renewcommand*\p@enumiii{\theenumi(\theenumii)}
+\renewcommand*\p@enumiv{\p@enumiii\theenumiii}
+\newcommand*\labelitemi{\textbullet}
+\newcommand*\labelitemii{\normalfont\bfseries \textendash}
+\newcommand*\labelitemiii{\textasteriskcentered}
+\newcommand*\labelitemiv{\textperiodcentered}
+\newenvironment*{description}
+               {\list{}{\labelwidth\z@ \itemindent-\leftmargin
+                        \let\makelabel\descriptionlabel}}
+               {\endlist}
+\newcommand*\descriptionlabel[1]{\hspace\labelsep
+                                \normalfont\bfseries #1}
+\newenvironment*{verse}
+               {\let\\\@centercr
+                \list{}{\setlength\itemsep{\z@skip}%
+                        \setlength\itemindent{-15\p@}%
+                        \setlength\listparindent{\itemindent}%
+                        \setlength\rightmargin{\leftmargin}%
+                        \addtolength\leftmargin{15\p@}}%
+                \item[]}
+               {\endlist}
+\newenvironment*{quotation}
+               {\list{}{\setlength\listparindent{1.5em}%
+                        \setlength\itemindent{\listparindent}%
+                        \setlength\rightmargin{\leftmargin}}%
+                \item[]}
+               {\endlist}
+\newenvironment*{quote}
+               {\list{}{\setlength\rightmargin{\leftmargin}}%
+                \item[]}
+               {\endlist}
+%    \end{macrocode}
+%
+%    \subsubsection{Miscellanea}
+%
+%    \begin{macrocode}
+\setlength\parindent{2em}
+\setlength\parskip{\z@ plus \p@}
+\setlength\columnsep{10\p@}
+\setlength\columnseprule{\z@}
+\setlength\arraycolsep{5\p@}
+\setlength\tabcolsep{6\p@}
+\setlength\arrayrulewidth{.4\p@}
+\setlength\doublerulesep{2\p@}
+\setlength\tabbingsep{\labelsep}
+\skip\@mpfootins = \skip\footins
+\setlength\fboxsep{3\p@}
+\setlength\fboxrule{.4\p@}
+\renewcommand*\theequation{\@arabic\c@equation}
+\DeclareOldFontCommand{\rm}{\normalfont\rmfamily}{\mathrm}
+\DeclareOldFontCommand{\sf}{\normalfont\sffamily}{\mathsf}
+\DeclareOldFontCommand{\tt}{\normalfont\ttfamily}{\mathtt}
+\DeclareOldFontCommand{\bf}{\normalfont\bfseries}{\mathbf}
+\DeclareOldFontCommand{\it}{\normalfont\itshape}{\mathit}
+\DeclareOldFontCommand{\sl}{\normalfont\slshape}{\relax}
+\DeclareOldFontCommand{\sc}{\normalfont\scshape}{\relax}
+\DeclareRobustCommand*{\cal}{\@fontswitch{\relax}{\mathcal}}
+\DeclareRobustCommand*{\mit}{\@fontswitch{\relax}{\mathnormal}}
+\renewcommand*\footnoterule{%
+  \kern-\p@
+  \hrule \@width .4\columnwidth
+  \kern .6\p@}
+\long\def\@makefntext#1{%
+    \noindent
+    \hangindent 5\p@
+    \hb@xt@5\p@{\hss\@makefnmark}#1}
+%    \end{macrocode}
+%
+%    \subsubsection{Names and final setup}
+%
+%    \begin{macrocode}
+\newcommand*\subjectname     {Oggetto:}
+\newcommand*\registeredname  {Raccomandata}
+\newcommand*\registeredRRname{\registeredname~A.R.}
+\newcommand*\andccname       {e~p.~c.}
+\newcommand*\ccname          {P.~c.:}
+\newcommand*\enclname        {Allegati:}
+\newcommand*\PSname          {P.S.:}
+\newcommand*\headtoname      {A:}
+\newcommand*\lettername      {Lettera}
+\newcommand*\today{\number\day~\ifcase\month\or
+  gennaio\or febbraio\or marzo\or aprile\or maggio\or giugno\or
+  luglio\or agosto\or settembre\or ottobre\or novembre\or dicembre\fi
+  \space\number\year}
+\let\do\@undefined
+\pagestyle{plain}
+\pagenumbering{arabic}
+\raggedbottom
+\onecolumn
+%    \end{macrocode}
+%
+%    End of the module for the \packlass{\letteracdp} class.
+%    \begin{macrocode}
+%</letter>
+%    \end{macrocode}
+%    \noindent\null\par
+%
+% \section{The code for the \protect\packlass{\articoletteracdp} class}
+%
+%    This part of the file goes into \filedir{\articoletteracdp.cls}.
+%    \begin{macrocode}
+%<*artico>
+%    \end{macrocode}
+%
+%    \subsection{Identification}
+%
+%    \begin{macrocode}
+\NeedsTeXFormat{LaTeX2e}[1996/06/01] % LaTeX2e is required!
+\ProvidesClass{articoletteracdp}
+              [2018/02/08 v0.36d (development)]
+%    \end{macrocode}
+%
+%    \subsection{Initial code}
+%
+%    We check that some names are not already taken.
+%    \begin{macrocode}
+\@ifdefinable\@out@table@list{}
+\@ifdefinable\@in@table@list{}
+\@ifdefinable\@do@tf{}
+\@ifdefinable\@sec@head@size{}
+%    \end{macrocode}
+%
+%    Definition of two switches that support the options about what to
+%    include in the table of contents.
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\newif#1}}
+\do\if@toc@in@toc@
+\do\if@loX@in@toc@
+%    \end{macrocode}
+%
+%    \begin{macro}{\@letter@bookmark}
+%    Support for pdf\TeX\slash\packlass{\HyperRef}.  If pdf\TeX\ is
+%    being used to typeset the document, if the \packlass{\HyperRef}
+%    package is loaded, and if the user doesn't ask us to avoid doing so,
+%    we shall generate a ``level~0'' bookmark for each letter we shall
+%    typeset (sections are of level~1, so they will be bookmarked under
+%    letters).  This command serves this purpose: it is defined either
+%    as "\@gobbletwo", if such bookmarks are \emph{not} being generated,
+%    or as a suitable invocation of "\pdfbookmark" if they are.  To begin
+%    with, we set the former alternative, which makes it act as a no-op.
+%    \begin{macrocode}
+\@ifdefinable\@letter@bookmark{\let\@letter@bookmark\@gobbletwo}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Space above and below captions for figures and tables.
+%    \begin{macrocode}
+\newlength\abovecaptionskip
+\newlength\belowcaptionskip
+%    \end{macrocode}
+%
+%    \subsection{Declaration of options}
+%
+%    \begin{macrocode}
+\DeclareOption{titlepage}{%
+  \@latexerr{No title page for letters}\@eha
+}
+\DeclareOption{notitlepage}{}
+\DeclareOption{loXintoc}{%
+  \@toc@in@toc@false
+  \@loX@in@toc@true
+}
+\DeclareOption{tocintoc}{%
+  \@toc@in@toc@true
+  \@loX@in@toc@true
+}
+\DeclareOption{Hofstadter}{%
+  \ExecuteOptions{tocintoc}%
+}
+\DeclareOption{plaintoc}{%
+  \@toc@in@toc@false
+  \@loX@in@toc@false
+}
+%    \end{macrocode}
+%    The option \opz{letterbookmarks} causes the bookmarks for letters to
+%    be generated.  Upon expansion, the 2~arguments of
+%    "\@letter@bookmark" will become arguments of "\pdfbookmark".  We
+%    also need to ask the \packlass{\HyperRef} package to generate closed
+%    bookmarks.  Note that the user can later overwrite this setting;
+%    note also that nothing will happen if \packlass{\HyperRef} is not
+%    loaded later.
+%    \begin{macrocode}
+\DeclareOption{letterbookmarks}{%
+  \def\@letter@bookmark{\pdfbookmark[0]}%
+  \PassOptionsToPackage{bookmarksopen=false}{hyperref}%
+}
+%    \end{macrocode}
+%    The option \opz{noletterbookmarks} supresses the bookmarks for
+%    letters.
+%    \begin{macrocode}
+\DeclareOption{noletterbookmarks}{%
+  \let\@letter@bookmark\@gobbletwo
+}
+%    \end{macrocode}
+%    The option \opz{openletterbookmarks} causes the bookmarks for
+%    letters to be generated and to be presented open to the reader.  We
+%    ask the \packlass{\HyperRef} package to generate open bookmarks, but
+%    only one level deep.  Note that the user can later overwrite this
+%    setting.  This is made the default option, below.
+%    \begin{macrocode}
+\DeclareOption{openletterbookmarks}{%
+  \def\@letter@bookmark{\pdfbookmark[0]}%
+  \PassOptionsToPackage{bookmarksopen,bookmarksopenlevel=1}{hyperref}%
+}
+\DeclareOption*{\PassOptionsToClass{\CurrentOption}{letteracdp}}
+%    \end{macrocode}
+%
+%    \subsection{Option processing}
+%
+%    \begin{macrocode}
+\ExecuteOptions{plaintoc,openletterbookmarks}
+\ProcessOptions\relax
+%    \end{macrocode}
+%
+%    \subsection{Class loading}
+%
+%    \begin{macrocode}
+\LoadClass{letteracdp}[2018/02/08]
+%    \end{macrocode}
+%
+%    \subsection{Main code}
+%
+%    Unfortunately, most of the code is not commented (yet).
+%
+%    \subsubsection{More initializations}
+%
+%    \begin{macrocode}
+\newcounter{section}[letter]
+\newcounter{paragraph}[section]
+\newcounter{figure}[letter]
+\newcounter{table}[letter]
+%    \end{macrocode}
+%
+%    Stuff for dealing with the \packlass{\HyperRef} package.  The problem is
+%    our non-standard hierarchy of sectioning commands, with paragraphs placed
+%    directly below sections.  In this version (0.34) we choose a different
+%    approach than the one we adopted in version 0.33, redefining
+%    "\theHparagraph"; of course, this must be done \emph{after}
+%    \packlass{\HyperRef} has been loaded, and we could not find any better
+%    place for this than the "\AtBeginDocument" hook.  Within the same hook, we
+%    also redefine "\theHsection" (the counter used by \packlass{\HyperRef} to
+%    generate hyperlinks to sections) so that sections with the same number, but
+%    included in different letters, will have different anchors; we fix the
+%    bookmark level for paragraphs, too.
+%    \begin{macrocode}
+\AtBeginDocument{%
+  \def\theHletter{\arabic{letter}}%
+  \@ifpackageloaded{hyperref}{%
+    \def\theHparagraph{\theHsection.\arabic{paragraph}}%
+    \def\theHsection{\theHletter.\arabic{section}}%
+    \def\toclevel@paragraph{2}%
+  }{%
+%    \end{macrocode}
+%    If the \packlass{\HyperRef} package is not loaded, we ensure that
+%    "\@letter@bookmarks" acts as a no-op:
+%    \begin{macrocode}
+    \let\@letter@bookmark\@gobbletwo
+  }%
+}
+%    \end{macrocode}
+%
+%    \begin{macro}{\hyper@last}
+%    The following line is to deactivate the check that
+%    \packlass{\HyperRef} makes against old files; this is necessary
+%    because otherwise, on the first \LaTeX\ run, it would overwrite our
+%    redefinition of "\@starttoc", possibly writing unwanted
+%    \filedir{.toc}, \filedir{.lof}, and \filedir{.lot} files, and (much
+%    worse) causing trouble if the letter happens to contain more than one
+%    "\tableofcontents", "\listoffigures", or "\listoftables".  Of
+%    course, this means that the user must be informed that (s)he has to
+%    delete the old files by hand.~\mbox{:-(}^^A ) paren match
+%    \closeofsentencespace Note, anyway, that the automatic check
+%    made by \packlass{\HyperRef} would not work with the \Bundle\ 
+%    in any case (because it looks for \filedir{.toc}, \filedir{.lof},
+%    etc.\ files, not for, say, \filedir{.toc1}, etc.), so\ldots
+%    \begin{macrocode}
+\@ifdefinable\hyper@last{\let\hyper@last\relax}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Back to uncommented code.
+%
+%    \begin{macrocode}
+%% Command \title and \author redefined to make changes local.
+\def\title#1{\def\@title{#1}}
+\def\author#1{\def\@author{#1}}
+%    \end{macrocode}
+%
+%    \subsubsection{Managing the \protect\filedir{.toc}, 
+%      \protect\filedir{.lof}, and \protect\filedir{.lot} files}
+%
+%    \begin{macrocode}
+%% Inner command \@starttoc redefined to make table of contents, etc.
+%% local to letters (this is tricky!).
+\def\@starttoc#1{%
+  \begingroup
+    \vskip\parskip
+    \parskip\z@skip
+    \makeatletter
+    \@input{\jobname.#1\number\c@letter}%
+    \if@filesw
+      \@ifundefined{tf@@#1}{%
+        \expandafter\newwrite\csname tf@@#1\endcsname
+      }\relax
+      \immediate\write\@out@table@list{\string\@do@tf{#1}}%
+    \fi
+    \@nobreakfalse
+  \endgroup
+}
+%    \end{macrocode}
+%
+%    The "\@cdp@begin@letter@hook" (new name in vers.~0.36d) macro is invoked
+%    whenever a letter starts; we want (possibly, see above) a bookmark to be
+%    generated for the letter.  Note that we use "\theletter" for the letter
+%    number presented to the user, and "\theHletter" for the number used to
+%    generate the anchor.
+%    \begin{macrocode}
+\g@addto@macro\@cdp@begin@letter@hook{%
+  \edef\@cdp@reserved{%
+    \noexpand\@letter@bookmark
+      {\lettername\space\theletter}{letter.\theHletter}%
+  }%
+  \@cdp@reserved
+%    \end{macrocode}
+%
+%    Actions for closing a set of toc/lof/lot file and opening another:
+%    \begin{macrocode}
+  \if@filesw
+    {\escapechar\m@ne
+      \immediate\write\@out@table@list{\string\}^^J\string\{}%
+    }%
+    \immediate\write\@auxout
+      {\string\@deferred@clopen{\number\c@letter}}%
+  \fi
+}
+%    \end{macrocode}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\@ifdefinable\@deferred@open  {\let\@deferred@open  \@gobble}
+\@ifdefinable\@deferred@close {\let\@deferred@close \@empty}
+\@ifdefinable\@deferred@clopen{\let\@deferred@clopen\@gobble}
+\newwrite\@out@table@list
+\newread\@in@table@list
+\AtBeginDocument{%
+  \if@filesw
+    \immediate\openout\@out@table@list = \jobname.summ\relax
+    {\escapechar\m@ne
+      \immediate\write\@out@table@list{\string\{}%
+    }%
+    \immediate\write\@auxout{\string\@deferred@open{0}}%
+    \def\@deferred@close{%
+      \def\@do@tf##1{%
+        \@restore@tf{##1}%
+        \immediate\closeout \csname tf@##1\endcsname
+        \global\expandafter\let\csname tf@##1\endcsname\@undefined
+      }%
+      \@temp@table@list
+    }%
+    \def\@deferred@open#1{%
+      \ifeof\@in@table@list\else
+        \read\@in@table@list to\@temp@table@list
+        \def\@do@tf##1{%
+          \@restore@tf{##1}%
+          \immediate\openout
+            \csname tf@##1\endcsname = \jobname.##1#1\relax
+        }%
+        \@temp@table@list
+      \fi
+    }%
+    \def\@deferred@clopen#1{%
+      \@deferred@close
+      \@deferred@open{#1}%
+    }%
+  \fi
+}
+\AtEndDocument{%
+  \if@filesw
+    {\escapechar\m@ne
+      \immediate\write\@out@table@list{\string\}}%
+    }%
+    \immediate\closeout\@out@table@list
+    \clearpage
+    \immediate\write\@auxout{\string\@deferred@close}%
+    \openin\@in@table@list = \jobname.summ\relax
+  \fi
+}
+\@ifdefinable\@restore@tf{\def\@restore@tf#1{%
+  \edef\@tempa{%
+    \let\csname tf@#1\endcsname\csname tf@@#1\endcsname
+  }%
+  \global\@tempa
+}}
+\@ifdefinable\@temp@table@list{\let\@temp@table@list\@empty}
+%    \end{macrocode}
+%
+%    \subsubsection{Adding punctuation to titles}
+%
+%    \begin{macrocode}
+\@ifdefinable\@addfullstop{\long\def\@addfullstop#1{%
+  {\nonfrenchspacing\ignorespaces#1\unskip
+  \ifnum \spacefactor>\@m \else.\fi \/}%
+}}
+\newcommand*\nopunct{\spacefactor 1001\relax}
+%    \end{macrocode}
+%
+%    \subsubsection{Floats}
+%
+%    \changes{0.36d}{2018 Feb 08}{The assignment of \texttt{\protect\bslash 
+%      c@topnumber} to \texttt{\protect\bslash c@dbltopnumber} has been made
+%      \texttt{\protect\bslash global}.}^^A
+%    \begin{macrocode}
+\setcounter{topnumber}{\tw@}
+\renewcommand\topfraction{.7}
+\setcounter{bottomnumber}{\@ne}
+\renewcommand\bottomfraction{.3}
+\setcounter{totalnumber}{\thr@@}
+\renewcommand\textfraction{.2}
+\renewcommand\floatpagefraction{.5}
+\global\c@dbltopnumber\c@topnumber
+\let\dbltopfraction\topfraction
+\let\dblfloatpagefraction\floatpagefraction
+\setlength  \floatsep           {\bigskipamount}
+\@msetlength\textfloatsep    {2}{\bigskipamount}
+\setlength  \intextsep          {\bigskipamount}
+\setlength  \dblfloatsep        {\bigskipamount}
+\@msetlength\dbltextfloatsep {2}{\bigskipamount}
+\setlength  \@fptop             {\z@ plus 1 fil}
+\setlength  \@fpsep             {1\bigskipamount plus 2 fil}
+\setlength  \@fpbot             {\z@ plus 1 fil}
+\setlength  \@dblfptop          {\@fptop}
+\setlength  \@dblfpsep          {\@fpsep}
+\setlength  \@dblfpbot          {\@fpbot}
+\setlength\abovecaptionskip{\medskipamount}
+\setlength\belowcaptionskip{\z@skip}
+%    \end{macrocode}
+%
+%    \subsubsection{Title, section heads, figures, bibliography\ldots}
+%
+%    \begin{macro}{\maketitle}
+%    Without the \packlass{\HyperRef} package, the "\maketitle" command can take
+%    the same optional argument as "\maketopdate", for specifying a short string
+%    to be prepended to the date; and in this case, the new "\place" declaration
+%    will be automatically honored.  But the former feature will break if
+%    \packlass{\HyperRef} is loaded, and no remedy seems feasible for this,
+%    since \packlass{\HyperRef} assumes that "\maketitle" hasn't got any
+%    arguments.  Note also that a period is automatically added to the title.
+%    \begin{macrocode}
+\newcommand*\maketitle{%
+  \begingroup
+    \renewcommand\thefootnote{\@fnsymbol\c@footnote}%
+    \def\thesenderaddress{\@author}%
+    \def\thesubject{\leavevmode\@addfullstop\@title}%
+    \let\@empty@sender\@empty
+    \let\@thanks\@empty
+    \makepresentation
+    \@thanks
+  \endgroup
+  \setcounter{footnote}{\z@}%
+  \maketopdate
+}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Uncommented code.
+%    \begin{macrocode}
+\setcounter{secnumdepth}{\tw@}
+\def\@seccntformat#1{\csname the#1\endcsname .\enspace}
+\ifcase \@ptsize\relax
+  \def\@sec@head@size{\@setfontsize\@sec@head@size\@xiipt{15}}
+\or
+  \def\@sec@head@size{\@setfontsize\@sec@head@size\@xiipt{17.4}}
+\or
+  \def\@sec@head@size{\@setfontsize\@sec@head@size\@xivpt{18.75}}
+\fi
+\newcommand*\section{\@startsection {section}{\@ne}%
+  {\z@}%
+  {-\bigskipamount}%
+  {\smallskipamount}%
+  {%
+    \normalfont
+    \noindent\null\@@par\nobreak\vskip-\baselineskip
+    \parskip\z@skip
+    \@sec@head@size\bfseries
+  }%
+}
+\newcommand*\paragraph{\@startsection{paragraph}{\tw@}%
+  {\z@}%
+  {-\medskipamount}%
+  {-.66667em}%
+  {\normalfont\normalsize\itshape\@addfullstop}%
+}
+\newcommand*\epilogue{%
+  \if@noskipsec \leavevmode \fi
+  \par
+  \if@nobreak
+    \everypar{}%
+  \else
+    \addpenalty\@secpenalty\addvspace\bigskipamount
+  \fi
+}
+\renewcommand*\thesection{\@arabic\c@section}
+\renewcommand*\theparagraph{\thesection.\@arabic\c@paragraph}
+\renewcommand*\thefigure{\@arabic\c@figure}
+\def\fps@figure{tbp}
+\def\ftype@figure{\@ne}
+\def\ext@figure{lof}
+\def\fnum@figure{\figurename~\thefigure}
+\newenvironment*{figure}
+               {\@float{figure}}
+               {\end@float}
+\newenvironment*{figure*}
+               {\@dblfloat{figure}}
+               {\end@dblfloat}
+\renewcommand*\thetable{\@arabic\c@table}
+\def\fps@table{tbp}
+\def\ftype@table{\tw@}
+\def\ext@table{lot}
+\def\fnum@table{\tablename~\thetable}
+\newenvironment*{table}
+               {\@float{table}}
+               {\end@float}
+\newenvironment*{table*}
+               {\@dblfloat{table}}
+               {\end@dblfloat}
+\long\def\@makecaption#1#2{%
+  \vskip\abovecaptionskip
+  \sbox\@tempboxa{\itshape \@addfullstop{#1: #2}}%
+  \ifdim \wd\@tempboxa >\hsize
+    \unhbox\@tempboxa\par
+  \else
+    \global \@minipagefalse
+    \hb@xt@\hsize{\hfil\box\@tempboxa\hfil}%
+  \fi
+  \vskip\belowcaptionskip
+}
+\newcommand*\@pnumwidth{1.55em}
+\newcommand*\@tocrmarg{2.55em}
+\newcommand*\@dotsep{4.5}
+\setcounter{tocdepth}{\@ne}
+\newcommand*\tableofcontents{%
+  \section*{\contentsname \sectionmark\contentsname}
+  \if@toc@in@toc@
+    \addcontentsline{toc}{section}{\protect\contentsname}%
+  \fi
+  \@starttoc{toc}%
+}
+\newcommand*\l@section{\@dottedtocline{\@ne}{\z@}{2em}}
+\newcommand*\l@paragraph[2]{%
+  \@dottedtocline{\tw@}{2em}{2.5em}{\small #1}{\small #2}%
+}
+\newcommand*\listoffigures{%
+  \section*{\listfigurename \sectionmark\listfigurename}%
+  \if@loX@in@toc@
+    \addcontentsline{toc}{section}{\protect\listfigurename}%
+  \fi
+  \@starttoc{lof}%
+}
+\def\l@figure{\@dottedtocline{\@ne}{\z@}{2em}}
+\newcommand*\listoftables{%
+  \section*{\listtablename \sectionmark\listtablename}%
+  \if@loX@in@toc@
+    \addcontentsline{toc}{section}{\protect\listtablename}%
+  \fi
+  \@starttoc{lot}%
+}
+\let\l@table\l@figure
+\newenvironment*{thebibliography}[1]{%
+  \startbreaks
+  \section*{\refname \sectionmark\refname}%
+  \addcontentsline{toc}{section}{\protect\refname}%
+  \vskip\parskip
+  \parskip\z@skip
+  \parindent\z@
+  \list{\@biblabel{\@arabic\c@enumiv}}{%
+    \settowidth\labelwidth{\@biblabel{#1}}%
+    \leftmargin\labelwidth
+    \advance\leftmargin\labelsep
+    \usecounter{enumiv}%
+    \let\p@enumiv\@empty
+    \renewcommand\theenumiv{\@arabic\c@enumiv}%
+  }%
+  \sloppy
+  \clubpenalty 4000   \@clubpenalty \clubpenalty
+  \widowpenalty 4000
+  \sfcode`\.\@m
+}{%
+  \def\@noitemerr
+    {\@latex@warning{Empty `thebibliography' environment}}%
+  \endlist
+}
+\newcommand*\newblock{\hskip .11em\@plus.33em\@minus.07em}
+\newcommand*\bysame{\leavevmode\hbox to3em{\hrulefill}\thinspace}
+%    \end{macrocode}
+%
+%    \subsubsection{Names}
+%
+%    \begin{macrocode}
+\newcommand*\contentsname  {Sommario}
+\newcommand*\listfigurename{Indice delle figure}
+\newcommand*\listtablename {Indice delle tabelle}
+\newcommand*\refname       {Testi citati}
+\newcommand*\indexname     {Indice analitico}
+\newcommand*\figurename    {Figura}
+\newcommand*\tablename     {Tabella}
+%    \end{macrocode}
+%
+%    End of the module for the \packlass{\articoletteracdp} class.
+%    \begin{macrocode}
+%</artico>
+%    \end{macrocode}
+%    \noindent\null\par
+%
+% \section{The code for the \protect\packlass{\cdpaddon} package}
+%
+%    This part of the file goes into \filedir{\cdpaddon.sty}.
+%    \begin{macrocode}
+%<*addon>
+%    \end{macrocode}
+%
+%    \subsection{Identification}
+%
+%    Why did I ask for the June 1998 release of \LaTeX?  I don't remember!
+%    \begin{macrocode}
+\NeedsTeXFormat{LaTeX2e}[1998/06/01] % LaTeX2e is required!
+\ProvidesPackage{cdpaddon}
+              [2018/02/08 v0.36d (development)]
+\@ifdefinable\@cdpaddon{\def\@cdpaddon{cdpaddon}}
+%    \end{macrocode}
+%
+%    \subsection{Initial code}
+%
+%    Switches; "\if@custom@lh@" added in vers.~0.36 (2015 Feb~08).
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable#1{\newif#1}}
+\do\if@using@cdp@
+\do\if@use@color@
+\do\if@use@hyper@
+\do\if@custom@lh@
+%    \end{macrocode}
+%
+%    \begin{macro}{\@cdpaddon@printer}
+%    Below, we shall store in this macro the name (without the extension
+%    \filedir{.def}) of the definition file from which to read the
+%    definitions of the colors for the C.D.P.  seal.
+%    If it is empty, the emergency colors will be used:
+%    we make this the default.
+%    \begin{macrocode}
+\@ifdefinable\@cdpaddon@printer{\let\@cdpaddon@printer\@empty}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    ``Scratch'' macros, will be re-used in the sequel.
+%    \begin{macrocode}
+\@ifdefinable\@temp@cdpaddon@a{}
+\@ifdefinable\@temp@cdpaddon@b{}
+%    \end{macrocode}
+%
+%    Here is a first use of those ``scratch'' macros.
+%    \begin{macrocode}
+\def\@temp@cdpaddon@a{%
+  \@using@cdp@false
+  \PackageWarningNoLine{\@cdpaddon}{%
+    It seems that you are not using the letteracdp\MessageBreak
+    document class; therefore no attempt will be made\MessageBreak
+    to modify letterheads and similar things%
+  }%
+}
+\def\@temp@cdpaddon@b{letteracdp}
+%    \end{macrocode}
+%    Double check to be absolutely sure that the \packlass{\letteracdp}
+%    class is loaded.
+%    \begin{macrocode}
+\@ifclassloaded{\@temp@cdpaddon@b}{%
+  \ifx\@letteracdp\@temp@cdpaddon@b
+    \@using@cdp@true
+  \else
+    \@temp@cdpaddon@a
+  \fi
+}{%
+  \@temp@cdpaddon@a
+}
+%    \end{macrocode}
+%
+%    \subsection{Declaration of options}
+%
+%    The following macro is needed to strip the prefix \opz{printer:}\
+%    from the option that selects which color definition file to load.
+%    Again, we use one of the ``scratch'' macro to save memory (the other
+%    ``scratch'' macro is used as well inside).
+%    \begin{macrocode}
+\def\@temp@cdpaddon@a#1printer:#2,#3\@@@{%
+  \def\@temp@cdpaddon@b{#1}%
+  \ifx\@temp@cdpaddon@b\@empty
+    \def\@cdpaddon@printer{#2}%
+  \else
+    \@unknownoptionerror
+  \fi
+}
+%    \end{macrocode}
+%    Vers.~0.36 (2015 Feb~08): modified the existing option so that they also
+%    deal with the new "\if@custom@lh@" switch\ldots
+%    \begin{macrocode}
+\DeclareOption{bw}{\@use@color@false\@custom@lh@false}
+\DeclareOption{color}{\@use@color@true\@custom@lh@false}
+\DeclareOption{hypertext}{\@use@hyper@true\@custom@lh@false}
+\DeclareOption{plaintext}{\@use@hyper@false\@custom@lh@false}
+%    \end{macrocode}
+%    \ldots~and added new \opz{customletterhead} option.
+%    \begin{macrocode}
+\DeclareOption{customletterhead}{%
+  \@use@color@false
+  \@use@hyper@false
+  \@custom@lh@true
+}
+%    \end{macrocode}
+%    Otherwise, we can have a \opz{printer:}\ldots\ option requesting a color
+%    definition file.
+%    \begin{macrocode}
+\DeclareOption*{%
+  \expandafter\@temp@cdpaddon@a\CurrentOption,printer:,\@@@%
+}
+%    \end{macrocode}
+%
+%    \subsection{Option processing}
+%
+%    \begin{macrocode}
+\ExecuteOptions{color,plaintext}
+\ProcessOptions\relax
+%    \end{macrocode}
+%    If the \opz{printer:Default} option has been specified, we want
+%    the same behavior as if no \opz{printer:}\ldots\ option had been
+%    specified at all.
+%    \begin{macrocode}
+\def\@temp@cdpaddon@a{Default}
+\ifx\@cdpaddon@printer\@temp@cdpaddon@a
+  \let\@cdpaddon@printer\@empty
+\fi
+%    \end{macrocode}
+%
+%    \subsection{Package loading}
+%
+%    \changes{0.34a}{2010 Jun 01}{Fixed up the use of dvips names in the
+%      \protect\packlass{\protect\cdpaddon} package (bug reported by Tommaso
+%      Gordini).}^^A
+%    V.~0.34a: fixed up the use of dvips names
+%    (bug reported by Tommaso Gordini).
+%    V.~0.36: also removed the ridiculous check for the presence of standard
+%    packages on the system!
+%    \begin{macrocode}
+\if@use@color@
+  \RequirePackage[dvipsnames]{color}
+\fi
+\if@use@hyper@
+  \RequirePackage{hyperref}
+\fi
+%    \end{macrocode}
+%
+%    \subsection{Main code}
+%
+%    Unfortunately, the code is only sparsely commented (at the moment).
+%
+%    \subsubsection{Redefinition of the seal, etc.}
+%
+%    Vers.~0.36 (2015 Feb~08): removed the "\@back@folding@tag" macro,
+%    now become unnecessary because of the introduction of the
+%    "\foldingtagrule" user command.
+%    We leave the code in place, but commented out, for documentation purposes.
+%\begin{verbatim}
+%\@ifdefinable\@back@folding@tag{\def\@back@folding@tag{%
+%  \if@do@fold@
+%    \raisebox{\@lh@folding@ht}[\z@][\z@]{%
+%      \makebox[\z@][l]{%
+%        \color{strong@col}%
+%        \dimen@ -\@lh@right@margin
+%        \advance\dimen@ 1cm%
+%        \kern\dimen@ \vbox{%
+%          \kern -.1\p@
+%          \hrule \@height .1\p@ \@depth .1\p@ \@width 5mm%
+%          \kern -.1\p@
+%        }%
+%      }%
+%    }%
+%  \fi
+%}}
+%\end{verbatim}
+%
+%    If the \packlass{\letteracdp} class is loaded\ldots
+%    \begin{macrocode}
+\if@using@cdp@
+%    \end{macrocode}
+%    \ldots then we can try to replace the macros that draw the seal,
+%    etc.; but we want to perform the redefinition (if and) only if the
+%    macro is already defined, and rise an error otherwise.  To ease this
+%    task, we define the ``scratch'' macro "\@temp@cdpaddon@a" in such a
+%    way that "\@temp@cdpaddon@a{"\meta{name}"}{"\meta{code}"}" rises an
+%    error if \meta{name} is undefined, and executes \meta{code}
+%    otherwise.  It is intended that \meta{code} is the code that does the
+%    actual redefinition.  Note that \meta{name} must be indicated
+%    \emph{without} the backslash.  Note also that it is not necessary
+%    a second parameter for \meta{code}: "{"\meta{code}"}" becomes the
+%    third parameter of "\@ifundefined".
+%    \begin{macrocode}
+  \def\@temp@cdpaddon@a#1{%
+    \@ifundefined{#1}{%
+      \PackageError\@cdpaddon{%
+        Internal command \@backslashchar#1 undefined%
+      }{%
+        The internal command \@backslashchar#1,
+        that should have been defined\MessageBreak
+        by the \@letteracdp\space document class,
+        is actually undefined.\MessageBreak
+        Probably, you are using an old or modified version
+        of that class.\MessageBreak
+%    \end{macrocode}
+%    Vers.~0.36 (2015 Feb~08): modified the following line:
+%    \begin{macrocode}
+        Proceed, but keep your fingers crossed!%
+      }%
+    }%
+  }
+%    \end{macrocode}
+%
+%    We first take care of color.  Did the user request colors?
+%    \begin{macrocode}
+  \if@use@color@
+%    \end{macrocode}
+%    Yes?  Well, in that case, we try to load the file that defines
+%    the hues.  First of all, see whether the user selected a color
+%    definition file.
+%    \begin{macrocode}
+    \ifx\@cdpaddon@printer\@empty
+%    \end{macrocode}
+%    If not (\("\@cdpaddon@printer"="\@empty"\)), then we must read the
+%    config.\ file.  Before doing this, we define the "\DeclareCDPSealHuesDefault"
+%    command, in a somewhat tricky way: we begin a group, thereby making
+%    a local definition, but we put the "\endgroup" in the replacement text
+%    of the macro itself.  This is quite OK, because once the macro has
+%    been expanded, we no longer need its definition!  We must foresee
+%    the case in which the configuration file does not contain any
+%    "\DeclareCDPSealHuesDefault" command at all.  For this, we use
+%    another hack: we "\let" "\@temp@cdpaddon@b" equal to "\endgroup"
+%    \emph{inside} the group, but to "\@empty" outside of it.  Then we call it:
+%    if the group has already ended, nothing happens, otherwise the group
+%    is ended now.
+%    \begin{macrocode}
+      \let\@temp@cdpaddon@b\@empty
+      \begingroup % \endgroup put in by \@temp@cdpaddon@b
+      \let\@temp@cdpaddon@b\endgroup
+      \InputIfFileExists{cdpshues.cfg}{%
+        \PackageInfo{\@cdpaddon}{%
+          Reading config. file%
+        }%
+%    \end{macrocode}
+%    \begin{macro}{\DeclareCDPSealHuesDefault}
+%    This command is defined in such a way that it not only ends the group,
+%    but also stops reading from the file.
+%    \begin{macrocode}
+        \def\DeclareCDPSealHuesDefault{%
+          \@temp@cdpaddon@b % ends group
+          \endinput
+%    \end{macrocode}
+%    \end{macro}
+%    The argument to "\DeclareCDPSealHuesDefault" will become the
+%    replacement text of the following "\def".
+%    \begin{macrocode}
+          \def\@cdpaddon@printer
+        }%
+      }{%
+        \PackageWarningNoLine{\@cdpaddon}{%
+          Could not find config. file for default printer%
+        }%
+      }%
+%    \end{macrocode}
+%    The following is part of the hack to end the group if it has not
+%    already ended.
+%    \begin{macrocode}
+      \@temp@cdpaddon@b
+%    \end{macrocode}
+%    We now check if the user specified the \opz{printer:None} option;
+%    if so, we take the same action that would result from an empty
+%    configuration file.
+%    \begin{macrocode}
+    \else
+      \def\@temp@cdpaddon@b{None}%
+      \ifx\@cdpaddon@printer\@temp@cdpaddon@b
+        \let\@cdpaddon@printer\@empty
+      \fi
+%    \end{macrocode}
+%    End of things to do when no \opz{printer:}\ldots\ option has been
+%    specified.
+%    \begin{macrocode}
+    \fi
+%    \end{macrocode}
+%    OK, now we have the name of the color definition file in
+%    "\@cdpaddon@printer", and we have to load it.  The following are the
+%    actions to take when the file cannot be found or when
+%    "\@cdpaddon@printer" is still empty (\emph{e.g.,} because no
+%    config.\ file was found, or because it was void): use emergency
+%    definitions and issue a warning.  We save them in a ``scratch''
+%    macro because we need them twice~(!).
+%    \begin{macrocode}
+    \def\@temp@cdpaddon@b{%
+      \definecolor{slight@col}{named}{SpringGreen}
+      \definecolor{strong@col}{named}{OliveGreen}
+      \PackageInfo{\@cdpaddon}{%
+        Color hues defined internally%
+      }%
+      \typeout{%
+        *Package cdpaddon using built-in colors for the C.D.P. seal.*%
+      }%
+    }
+%    \end{macrocode}
+%    We finally try to load the color definition file.
+%    \begin{macrocode}
+    \ifx\@cdpaddon@printer\@empty
+      \@temp@cdpaddon@b
+    \else
+      \InputIfFileExists{\@cdpaddon@printer.def}{%
+        \PackageInfo{\@cdpaddon}{%
+          Color hues defined by def. file\MessageBreak
+          \@cdpaddon@printer.def%
+        }%
+      }{%
+        \PackageWarningNoLine{\@cdpaddon}{%
+          Could not find def. file \@cdpaddon@printer.def%
+        }%
+        \@temp@cdpaddon@b
+      }%
+    \fi
+%    \end{macrocode}
+%
+%    We define another handy subroutine.  Given the name \meta{boxname}
+%    of an hbox, "\@temp@cdpaddon@b{"\meta{boxname}"}" causes a
+%    "\color{strong@col}" declaration to be added at the beginning of
+%    "\"\meta{boxname}, properly contained in a group to ensure that the
+%    "\special" for restoring the previous colors is included in the box too.
+%    We use this method of setting and resetting the color inside the
+%    individual boxes because the one used in the previous versions, of
+%    setting the color once for all at the beginning of "\@cdp@head", did
+%    not seem to work properly with pdf\TeX.
+%    \begin{macrocode}
+    \def\@temp@cdpaddon@b#1{%
+      \@temp@cdpaddon@a{#1}{%
+        \setbox\z@\box\@nameuse{#1}%
+        \sbox{\@nameuse{#1}}{{\color{strong@col}\unhbox\z@}}%
+      }%
+    }
+%    \end{macrocode}
+%
+%    Actual redefinition of macros begins here.
+%
+%    Vers.~0.36 (2015 Feb~08): no need, now, to redefine the "\@folding@tag"
+%    macro: just redefine the user-level command "\foldingtagrule"
+%    (much neater!).
+%    \begin{macrocode}
+    \renewcommand*\foldingtagrule{%
+      \color{strong@col}%
+      \CDPFactoryFoldingTagRule
+    }
+%    \end{macrocode}
+%
+%    \begin{macro}{\@logo@box@base}
+%    \changes{0.32}{2002 Jul 01}{Eliminated an awful bug introduced with
+%      version 0.31 (a conditional that could not appear at this spot).}^^A
+%    Color the main part of the seal.
+%    \begin{macrocode}
+    \@temp@cdpaddon@a{@logo@box@base}{%
+      \savebox\@logo@box@base[\z@][r]{\setlength\unitlength{.625mm}%
+        \begin{picture}(32,16)(-3,7.87)%
+%    \end{macrocode}
+%    I don't remember exactly what this group was for.  Eliminate?
+%    \begin{macrocode}
+          \begingroup
+%    \end{macrocode}
+%    Draw the inner of the~``D'' and of the~``P'', in the slight color.
+%    \begin{macrocode}
+            \color{slight@col}%
+%    \end{macrocode}
+%    Try to draw two filled circles of the right size to fill up the
+%    inner of the two letters.  If the target system happens to have 
+%    sufficiently large filled circles, this will suffice.
+%    \begin{macrocode}
+            \put(8,16){\circle*{10}}%
+            \put(18,16){\circle*{10}}%
+%    \end{macrocode}
+%    With the standard set of fonts, however, the above request can not
+%    be honored, and the two circles we have just obtained are a little
+%    too small; so, we finish them by adding arcs of circumference of
+%    increasing size, drawn in thick lines.
+%    \begin{macrocode}
+            \thicklines
+            \put(8,16){\oval(8.2,8.2)[l]}%
+            \put(8,16){\oval(8.6,8.6)[l]}%
+            \put(8,16){\oval(9,9)[l]}%
+            \put(8,16){\oval(9.4,9.4)[l]}%
+            \put(8,16){\oval(9.8,9.8)[l]}%
+            \put(18,16){\oval(8.2,8.2)[r]}%
+            \put(18,16){\oval(8.6,8.6)[r]}%
+            \put(18,16){\oval(9,9)[r]}%
+            \put(18,16){\oval(9.4,9.4)[r]}%
+            \put(18,16){\oval(9.8,9.8)[r]}%
+%    \end{macrocode}
+%    Now erase the inner half of the two circles.
+%    \begin{macrocode}
+            \put(13,16){\makebox(0,0){\color{white}%
+              \vrule height 6.25mm depth 0mm width 6.25mm
+            }}%
+%    \end{macrocode}
+%    Draw the vertical part of the two letters.
+%    \begin{macrocode}
+            \put(9,11){\makebox(0,0)[bl]{%
+              \vrule height 12.5mm depth 0mm width 1.875mm
+            }}%
+            \put(14,1){\makebox(0,0)[bl]{%
+              \vrule height 12.5mm depth 0mm width 1.875mm
+            }}%
+          \endgroup
+%    \end{macrocode}
+%    Now redraw the outer strokes of the~``D'' and of the~``P'' in the
+%    strong color.
+%    \begin{macrocode}
+          \color{strong@col}%
+          \put(8,16){\oval(10,10)[l]}%
+          \put(8,11){\line(0,1){10}}%
+          \put(9,11){\framebox(3,20){}}%
+          \put(18,16){\oval(10,10)[r]}%
+          \put(18,11){\line(0,1){10}}%
+          \put(14,1){\framebox(3,20){}}%
+%    \end{macrocode}
+%    The strokes of the~``C'' are thick.
+%    \begin{macrocode}
+          \thicklines
+          \put(8,16){\oval(16,16)[l]}%
+          \put(8,8){\line(1,0){5}}%
+          \put(13,24){\line(1,0){10}}%
+          \put(8,16){\oval(14,14)[l]}%
+          \put(8,9){\line(1,0){5}}%
+          \put(13,23){\line(1,0){10}}%
+        \end{picture}%
+      }%
+    }
+%    \end{macrocode}
+%    \end{macro}
+%    Coloring the other parts of the seal is easier: just add the color
+%    declaration to the various boxes, to the rule in the head, and to the
+%    whole footer.
+%    \begin{macrocode}
+    \@temp@cdpaddon@b{@logo@box@addS}
+    \@temp@cdpaddon@b{@logo@box@addL}
+    \@temp@cdpaddon@b{@oordinamento@box}
+    \@temp@cdpaddon@a{@cdp@head}{\def\@cdp@head{%
+      \@logo@overlay\@logo@box@addL
+      \copy\@oordinamento@box
+      {\color{strong@col}\hrulefill}\kern\@lh@right@margin
+    }}
+    \@temp@cdpaddon@a{@cdp@foot}{\def\@cdp@foot{%
+      \color{strong@col}%
+      \reset@font
+      \setlength\@tempdima{\textwidth}%
+      \addtolength\@tempdima{-2\@lh@right@margin}%
+      \hss\parbox[t]{\@tempdima}{%
+        \parfillskip\z@skip
+        \noindent\hrulefill\@@par
+        \baselineskip 11\p@
+        \hb@xt@\hsize{\hfil\copy\@name@and@WWW@box\hfil}%
+      }\hss
+    }}
+  \fi
+%    \end{macrocode}
+%
+%    Support for user-defined letterheads added in vers.~0.36 (2015 Feb~08).
+%    Support for custom logo (cf.~\sty{logo} pagestyle and its relatives)
+%    still kept hidden.
+%
+%    First, define storage boxes to hold custom head, foot, and logo.
+%    \begin{macrocode}
+  \newsavebox\@cdp@custom@lhead@box
+  \newsavebox\@cdp@custom@lfoot@box
+  \newsavebox\@cdp@custom@llogo@box
+%    \end{macrocode}
+%
+%    \begin{environment}{customletterhead}
+%    \begin{environment}{customletterfoot}
+%    \begin{environment}{customletterlogo}
+%    These three environments are defined similarly, so we use one of the
+%    ``scratch'' macros to perform their definition
+%    The parameters are:
+%    \begin{paramlist}
+%      \param
+%        \( \texttt{head} \mathbin{|} \texttt{foot} \mathbin{|}
+%        \texttt{logo} \);\\
+%      \param
+%        intended alignment of the \env{minipage}
+%        (\( \texttt{b} \mathbin{|} \texttt{t} \));\\
+%      \param
+%        either "\vss" or nothing;\\
+%      \param
+%        either "\vss" or nothing.
+%    \end{paramlist}
+%    \begin{macrocode}
+  \def\@temp@cdpaddon@b#1#2#3#4{%
+    \newenvironment*{customletter#1}[1]{%
+%    \end{macrocode}
+%    Save in the appropriate box, pretending that they have zero height and
+%    depth\ldots
+%    \begin{macrocode}
+      \setbox\@nameuse{@cdp@custom@l#1@box}\vbox to\z@ \bgroup
+        \hsize ##1\relax
+        \parskip \z@skip
+        #3% either \vss or nothing
+%    \end{macrocode}
+%    \ldots~the contents of a temporary \env{minipage}; note that we need to
+%    disable the ``"Missing \begin{document}"'' error, which is triggered by
+%    "\everypar".
+%    \begin{macrocode}
+        \everypar{}%
+        \noindent\minipage[#2]{##1}%
+          \null
+    }{%
+%    \end{macrocode}
+%    Code for ending the \env{minipage}: note that we smash to zero the 
+%    possible depth of the contents.
+%    \begin{macrocode}
+          \par
+          \vskip -\baselineskip
+          \null
+        \endminipage
+        #4% either \vss or nothing
+      \egroup
+%    \end{macrocode}
+%    ``Lift'' the definition out of the group implied by the environment.
+%    We have used the outer boxes, above, because we prefer not to keep around
+%    any ``scratch'' boxes (\emph{e.g.}, "\box1") when we must pass control to
+%    the final user.
+%    \begin{macrocode}
+      \global \setbox \@ne \box \@nameuse{@cdp@custom@l#1@box}%
+      \xdef\@cdp@reserved{%
+        \setbox \@nameuse{@cdp@custom@l#1@box}\box \@ne
+      }%
+      \aftergroup \@cdp@reserved
+    }%
+  }%
+%    \end{macrocode}
+%    Perform definitions of the three abovementioned environments.
+%    \begin{macrocode}
+  \@temp@cdpaddon@b{head}{b}{\vss}{}
+  \@temp@cdpaddon@b{foot}{t}{}{\vss}
+  \@temp@cdpaddon@b{logo}{b}{\vss}{}
+%    \end{macrocode}
+%    \end{environment}
+%    \end{environment}
+%    \end{environment}
+%
+%    \begin{macro}{\ruleacrossheadorfoot}
+%    Draw a rule across head or foot.  Synopsis:
+%    \begin{flushleft}
+%      "\ruleacrossheadorfoot["\meta{wdth\_l}"]["\meta{wdth\_r}"]"
+%    \end{flushleft}
+%    \meta{wdth\_l} is the inset from the left margin (defaults to zero),
+%    a negative inset causes the rule to protrude into the margin itself;
+%    \meta{wdth\_r} is the inset from the right margin (defaults to
+%    \meta{wdth\_l}).  Both \meta{wdth\_l} and \meta{wdth\_r} must be
+%    rigid lengths.  \emph{Note:} "\@tempdima" and "\@tempdimb" are used here.
+%    \begin{macrocode}
+  \newcommand*\ruleacrossheadorfoot[1][\z@]{\par
+    \setlength\@tempdima{#1}%
+    \@ifnextchar [% ] bracket matching
+      \@cdp@rule@across@x
+      {%
+        \@tempdimb \@tempdima
+        \@cdp@rule@across
+      }%
+  }
+%    \end{macrocode}
+%    \end{macro}
+%
+%    Inner implementation.
+%    \begin{macrocode}
+  \@ifdefinable\@cdp@rule@across@x{\def\@cdp@rule@across@x[#1]{%
+    \setlength\@tempdimb{#1}%
+    \@cdp@rule@across
+  }}
+  \@ifdefinable\@cdp@rule@across{\def\@cdp@rule@across{
+    \nobreak
+    \vskip -\baselineskip
+    \hb@xt@ \hsize {%
+      \kern \@tempdima \hrulefill \kern \@tempdimb
+    }%
+  }}
+%    \end{macrocode}
+%
+%    If the \opz{customletterhead} option is in force, install custom
+%    head\slash foot\slash logo.
+%    \begin{macrocode}
+  \if@custom@lh@
+    \@temp@cdpaddon@a{@cdp@head}{\def\@cdp@head{%
+      \hss\copy\@cdp@custom@lhead@box\hss
+    }}
+    \@temp@cdpaddon@a{@cdp@foot}{\def\@cdp@foot{%
+      \hss\copy\@cdp@custom@lfoot@box\hss
+    }}
+%    \end{macrocode}
+%    \changes{0.36d}{2018 Feb 08}{Changed \texttt{\protect\bslash hb@xt@ 
+%      \protect\bslash z@\protect\symbol{`\{}\protect\bslash
+%      hss}\,\ldots\texttt{\protect\symbol{`\}}} to \texttt{\protect\bslash
+%      llap\protect\symbol{`\{}}\,\ldots\texttt{\protect\symbol{`\}}} in the
+%      code that typesets the custom logo.}^^A
+%    The logo is assumed to protrude to the left of the header
+%    ("\llap" used in v.~0.36d).
+%    \begin{macrocode}
+    \@temp@cdpaddon@a{@cdp@logo}{\def\@cdp@logo{%
+      \llap{\copy\@cdp@custom@llogo@box}%
+    }}
+%    \end{macrocode}
+%    Do not forget to reset "\longindentation"!
+%    \begin{macrocode}
+    \setlength\longindentation{.5\textwidth}
+  \fi
+%    \end{macrocode}
+%
+%    We now deal with hyperlinks.  If the user requested them\ldots
+%    \begin{macrocode}
+  \if@use@hyper@
+%    \end{macrocode}
+%    \ldots well, we take care of them.  The precompilation of the footer must
+%    be deferred until the "\begin{document}" hook, because the macros of the
+%    \packlass{\HyperRef} package are not available for actual typesetting until
+%    that moment.  Note that here we only add the "\href" command: the
+%    color-switching has already been taken care of inside the "\@cdp@foot" box
+%    (the use of color is independent of the use of hyperlinks).
+%    \changes{0.36d}{2018 Feb 08}{Added selection of OT1 font encoding to the 
+%      code that presets the ``hyperlink'' version of
+%      \texttt{\protect\bslash @name@and@WWW@box}.}^^A
+%    Vers.~0.36d: added "\fontencoding{OT1}\selectfont".
+%    \begin{macrocode}
+    \AtBeginDocument{%
+      \@temp@cdpaddon@a{@name@and@WWW@box}{%
+        \setbox\@name@and@WWW@box = \vtop{%
+          \baselineskip 11\p@
+          \fontencoding{OT1}\selectfont
+          \hb@xt@\z@{\hss \@lh@rm\Coordinamento \hss}%
+          \hb@xt@\z@{%
+            \hss
+            \@lh@it World Wide Web:\/
+            \href{\CoordinamentoWWW}{\@lh@tt \CoordinamentoWWW}%
+            \hss
+          }%
+        }%
+      }%
+%    \end{macrocode}
+%    In this case we must defer releasing "\@temp@cdpaddon@a" until
+%    "\begin{document}".
+%    \begin{macrocode}
+      \let\@temp@cdpaddon@a\@undefined
+    }
+%    \end{macrocode}
+%    The following line has been removed from the code, since the
+%    bookmark level for paragraphs is now fixed in the file
+%    \filedir{\articoletteracdp.cls} (v.~0.34).
+%\begin{verbatim}
+%\def\toclevel@paragraph{2}
+%\end{verbatim}
+%    If hyperlinks are not requested, we can release "\@temp@cdpaddon@a"
+%    right now.
+%    \begin{macrocode}
+  \else
+    \let\@temp@cdpaddon@a\@undefined
+  \fi
+%    \end{macrocode}
+%
+%    We can do the same thing if the \packlass{\letteracdp} class is
+%    not loaded.
+%    \begin{macrocode}
+\else
+  \let\@temp@cdpaddon@a\@undefined
+\fi
+%    \end{macrocode}
+%
+%    The memory taken by the following ``scratch'' macros can be freed
+%    in any case.
+%    \begin{macrocode}
+\let\if@using@cdp@\@undefined
+\let\@using@cdp@true\@undefined
+\let\@using@cdp@false\@undefined
+\let\if@use@color@\@undefined
+\let\@use@color@true\@undefined
+\let\@use@color@false\@undefined
+\let\if@use@hyper@\@undefined
+\let\@use@hyper@true\@undefined
+\let\@use@hyper@false\@undefined
+%    \end{macrocode}
+%    Vers.~0.36 (2015 Feb~08): added the following three lines\ldots
+%    \begin{macrocode}
+\let\if@custom@lh@\@undefined
+\let\@custom@lh@true\@undefined
+\let\@custom@lh@false\@undefined
+%    \end{macrocode}
+%    \ldots~and removed the following one:
+%\begin{verbatim}
+%\let\@back@folding@tag\@undefined
+%\end{verbatim}
+%    \begin{macrocode}
+\let\@cdpaddon@printer\@undefined
+\let\@temp@cdpaddon@b\@undefined
+%    \end{macrocode}
+%
+%    \subsubsection{Smiling faces}
+%
+%    \begin{macro}{\facesmile}
+%    \begin{macro}{\facefrown}
+%    These commands produce happy or sad ``faces''.  They are made
+%    ``transparent'' to the "\spacefactor", just like parentheses
+%    (the "\spacefactor" is saved in "\count@").
+%    \begin{macrocode}
+\DeclareRobustCommand*\facesmile{\@face\smile}
+\DeclareRobustCommand*\facefrown{\@face\frown}
+%    \end{macrocode}
+%    \end{macro}
+%    \end{macro}
+%
+%    \begin{macro}{\@face}
+%    The low-level command that draws the face ("\bigcirc"), the eyes,
+%    and the mouth: the latter is passed as an argument, so it can be
+%    either a "\smile" or a "\frown".
+%    \begin{macrocode}
+\@ifdefinable\@face{\def\@face#1{%
+  \leavevmode
+  \count@\spacefactor
+  \hb@xt@ 1em{\hfil$%
+    \hb@xt@\z@ {\hss$\bigcirc$\hss}%
+    \lower .2ex \hb@xt@\z@ {\hss$\scriptscriptstyle #1$\hss}%
+    \raise .3ex \hb@xt@\z@ {\hss${\cdot}\mkern 2mu{\cdot}$\hss}%
+  $\hfil}%
+  \spacefactor\count@
+}}
+%    \end{macrocode}
+%    \end{macro}
+%
+%    End of the module for the \packlass{\cdpaddon} package.
+%    \begin{macrocode}
+%</addon>
+%    \end{macrocode}
+%    \noindent\null\par
+%
+% \section{The code for the \protect\packlass{\cdpbabel} package}
+%
+%    This part of the file goes into \filedir{\cdpbabel.sty}.
+%    \begin{macrocode}
+%<*babel>
+%    \end{macrocode}
+%
+%    \subsection{Identification}
+%
+%    As usual, the reason for requesting this specific version of \LaTeXe\ is
+%    shrouded in mystery\ldots
+%    \begin{macrocode}
+\NeedsTeXFormat{LaTeX2e}[1998/09/02] % LaTeX2e is required!
+\ProvidesPackage{cdpbabel}
+                [2018/02/08 v0.36d (development)]
+\@ifdefinable\@cdpbabel{\def\@cdpbabel{cdpbabel}}
+%    \end{macrocode}
+%
+%    \subsection{Initial code}
+%
+%    Usual check for availability of names.
+%    \begin{macrocode}
+\def\do#1{\@ifdefinable #1{\let #1\@empty}}
+\do\@cdpbabel@perform@redefinitions
+\do\@cdpbabel@letter@names
+\do\@cdpbabel@artlet@names
+%    \end{macrocode}
+%
+%    \subsection{Declaration of options}
+%
+%    Options specify which languages should be activated.  A language option is
+%    both passed on to the \packlass{\babel} package and used to select and
+%    load a ``C.D.P. language definition file''.
+%    \begin{macrocode}
+\DeclareOption*{%
+  \IfFileExists{cdpnames\CurrentOption.ldf}{%
+    \input{cdpnames\CurrentOption.ldf}%
+%    \end{macrocode}
+%    If \( "\CurrentOption" = \mbox{\opz{italian}} \), say,
+%    then the following amounts to
+%\begin{verbatim}
+%\def\do#1{\g@addto@macro\@cdpbabel@perform@redefinitions{%
+%    \addto\captionsitalian{#1}%
+%}}
+%\end{verbatim}
+%    which is used just below with parameter~\#1 set equal to
+%    \emph{the expansion of} either "\@cdpbabel@letter@names" or
+%    "\@cdpbabel@artlet@names".
+%    \begin{macrocode}
+    \edef\do##1{%
+      \noexpand\g@addto@macro
+        \noexpand\@cdpbabel@perform@redefinitions
+        {%
+          \noexpand\addto \csname captions\CurrentOption \endcsname
+            {##1}%
+        }%
+    }%
+    \@ifclassloaded{letteracdp}{%
+      \expandafter\do \expandafter{\@cdpbabel@letter@names}%
+    }{}%
+    \@ifclassloaded{articoletteracdp}{%
+      \expandafter\do \expandafter{\@cdpbabel@artlet@names}%
+    }{}%
+    \PackageInfo{\@cdpbabel}{%
+      Redefined the names of "C.D.P. Bundle" captions\MessageBreak
+      for the language `\CurrentOption'%
+    }%
+  }{%
+    \PackageError{\@cdpbabel}{%
+      Name def. file `cdpnames\CurrentOption.ldf' not found%
+    }{%
+      Files of the form `cdpnames<language>.ldf' are meant
+      to define the names\MessageBreak
+      in the language <language> of some captions used by
+      the "C.D.P. Bundle".\MessageBreak
+      You requested\MessageBreak
+      \space\space<language> = `\CurrentOption',\MessageBreak
+      but the corresponding file is missing; therefore,
+      probably some of these\MessageBreak
+      captions will not be printed as intended.\MessageBreak
+      This error affects only the \@cdpbabel\space package,
+      but not the babel package.\MessageBreak
+      You may continue:
+      type \space <return> \space to proceed.%
+    }%
+  }%
+  \PassOptionsToPackage{\CurrentOption}{babel}%
+}
+%    \end{macrocode}
+%
+%    \subsection{Option processing}
+%
+%    \mbox{$*$-form} of "\ProcessOptions" required here.
+%    \begin{macrocode}
+\ProcessOptions*
+%    \end{macrocode}
+%    Now, the following are no longer needed.
+%    \begin{macrocode}
+\let \do = \@undefined
+\let \@cdpbabel@letter@names = \@undefined
+\let \@cdpbabel@artlet@names = \@undefined
+%    \end{macrocode}
+%
+%    \subsection{Package loading}
+%
+%    Note that the \packlass{\cdpbabel} package is loaded \emph{instead} of
+%    \packlass{\babel}.
+%    \begin{macrocode}
+\RequirePackage{babel}
+%    \end{macrocode}
+%
+%    \subsection{Main code}
+%
+%    At this point, "\@cdpbabel@perform@redefinitions" contains exactly the 
+%    set of "\addto\captions"\meta{language}"{"\ldots"}" commands that need
+%    to be executed for the languages that have been specified in the options.
+%    So, execute them.
+%    \begin{macrocode}
+\@cdpbabel@perform@redefinitions
+%    \end{macrocode}
+%    After that, "\@cdpbabel@perform@redefinitions" is no longer needed.
+%    \begin{macrocode}
+\let \@cdpbabel@perform@redefinitions = \@undefined
+%    \end{macrocode}
+%
+%    End of the module for the \packlass{\cdpbabel} package.
+%    \begin{macrocode}
+%</babel>
+%    \end{macrocode}
+%    \noindent\null\par
+%
+% \section{Definition and configuration files}
+%
+%    This section contains the ancillary files (definition and
+%    configuration files) used by the \packlass{\cdpaddon} and
+%    the \packlass{\cdpbabel} packages.
+%
+%    \subsection{The \protect\filedir{\example} file}
+%
+%    This part of the file goes into the prototype definition file
+%    \filedir{\example}.  All comments are left in the code because this
+%    file is intended as an example of how to write color definition files
+%    for the \packlass{\cdpaddon} package.
+%    \begin{macrocode}
+%<*example>
+%%%
+%%% The "\ProvidesFile" command allows LaTeX to check the name and
+%%% the release date of the file; if either differs from what the
+%%% user requested, a warning is issued when the file is loaded.
+%%% This helps to pinpoint old files as well as files which have been
+%%% installed incorrectly.  It is not mandatory to include this
+%%% command in a file, and you can omit it from your definition files
+%%% if you want (but including it is more elegant); however, if you do
+%%% leave this command in your definition files, you should modify
+%%% both its mandatory and its optional argument so that they reflect
+%%% the name and the release date, respectively, of your file.
+%%% Note that the extension ".def" must be included in the file name,
+%%% and that the date is in the format YYYY/MM/DD.
+\ProvidesFile{cdpshues-example.def}[2018/02/08 Printer-dependent file]
+%%%
+%%% Define here the colors to use to draw the C.D.P. seal;
+%%% "slight@col" is the color used to paint the inner of the D and
+%%% of the P, "strong@col" is the color used to draw the lines.
+%%% The colors are defined by means of the usual "\definecolor"
+%%% command, which is part of the standard color package.  The colors
+%%% defined here, of course, are just a silly example.
+\definecolor{slight@col}{named}{SpringGreen}
+\definecolor{strong@col}{named}{OliveGreen}
+%</example>
+%    \end{macrocode}
+%
+%    \subsection{The \protect\filedir{\epson} file}
+%
+%    This part of the file goes into the definition file
+%    \filedir{\epson}.
+%    \begin{macrocode}
+%<*epson>
+\ProvidesFile{epson-stylus-740.def}[2018/02/08 Printer-dependent file]
+\definecolor{slight@col}{rgb}{.8,1,.8}
+\definecolor{strong@col}{rgb}{0,.266667,0}
+%</epson>
+%    \end{macrocode}
+%
+%    \subsection{The \protect\filedir{\hplj} file}
+%
+%    This part of the file goes into the definition file \filedir{\hplj}.
+%    \begin{macrocode}
+%<*hplj>
+\ProvidesFile{hp-laserjet-4500.def}[2018/02/08 Printer-dependent file]
+\definecolor{slight@col}{cmyk}{.1,0,.1,0}
+\definecolor{strong@col}{cmyk}{.5,0,.5,.5}
+%</hplj>
+%    \end{macrocode}
+%
+%    \subsection{The \protect\filedir{\cdpshues} file}
+%
+%    This part of the file goes into the configuration file
+%    \filedir{\cdpshues}.  Again, we leave all comments in the generated
+%    file because they are meant to help the final user to modify the file.
+%    \begin{macrocode}
+%<*config>
+%%%
+%%% The argument of the "\DeclareCDPSealHuesDefault" command contains
+%%% the name (w/o extension) of the default color definition file:
+\DeclareCDPSealHuesDefault{cdpshues}
+
+====================
+EXPLANATORY COMMENTS
+====================
+
+This file is special in that the cdpaddon package stops reading it as
+soon as it encounters the first "\DeclareCDPSealHuesDefault" command:
+all subsequent lines are ignored, and can hence contain explanatory
+comments, just like these.  To save disk space (although, in this era
+of terabytes, this is not a compelling issue!), you can, if you want,
+delete all lines in this file except the one which contains the first
+occurrence of a "\DeclareCDPSealHuesDefault" command (12 lines above);
+but if you do so, please be sure to read them before deleting them!
+(Anyway, I think it is a good idea to leave the comments in place.)
+
+The "\DeclareCDPSealHuesDefault" command has one argument, in which
+you should put the name of a default file from which the definitions
+of the hues for the C.D.P. seal are read when no other file has been
+indicated in the options passed to the cdpaddon package.  Note that
+the extension ".def" is automatically added to the name; therefore,
+you **must** leave it out in the name given as the argument of the
+"\DeclareCDPSealHuesDefault" command.
+
+The C.D.P. Bundle comes with some definition files already included;
+their names are listed below, without the extension ".def" (each one
+is packaged in a "\DeclareCDPSealHuesDefault" command):
+
+\DeclareCDPSealHuesDefault{cdpshues-example}
+\DeclareCDPSealHuesDefault{epson-stylus-740}
+\DeclareCDPSealHuesDefault{hp-laserjet-4500}
+
+To make one of these files the default one, copy (or move) the line
+containing its name to the top of the file, so that its becomes the
+first line (yes, even above the opening comments, those four dozens
+lines starting with "%%": let us keep things easy!).
+
+If you write a new definition file, you can make it the default by
+writing a similar "\DeclareCDPSealHuesDefault" command and putting it
+in the first line of this file (above the opening comments, why not).
+Remember that only the first such command appearing in this file is
+taken into consideration: all subsequent lines are ignored.
+
+%</config>
+%    \end{macrocode}
+%
+%    \subsection{The \protect\filedir{\cdpnamesenglish} file}
+%
+%    This part of the file goes into the language definition file
+%    \filedir{\cdpnamesenglish}.
+%    \begin{macrocode}
+%<*lang-en>
+\ProvidesFile{cdpnamesenglish.ldf}[2018/02/08]
+\def\@cdpbabel@letter@names{%
+  \def\subjectname      {Subject:}%
+  \def\registeredname   {Registered}%
+  \def\registeredRRname {\registeredname~R.R.}%
+  \def\andccname        {cc}%
+  \def\ccname           {cc:}%
+  \def\enclname         {Encl:}%
+  \def\PSname           {P.S.:}%
+  \def\headtoname       {To:}%
+  \def\lettername       {Letter}%
+}
+\def\@cdpbabel@artlet@names{%
+  \def\contentsname     {Contents}%
+  \def\listfigurename   {List of figures}%
+  \def\listtablename    {List of tables}%
+%%  \def\refname          {References}%
+%%  \def\indexname        {Index}%
+%%  \def\figurename       {Figure}%
+%%  \def\tablename        {Table}%
+}
+%</lang-en>
+%    \end{macrocode}
+%
+%    \subsection{The \protect\filedir{\cdpnamesitalian} file}
+%
+%    This part of the file goes into the language definition file
+%    \filedir{\cdpnamesitalian}.
+%    \begin{macrocode}
+%<*lang-it>
+\ProvidesFile{cdpnamesitalian.ldf}[2018/02/08]
+\def\@cdpbabel@letter@names{%
+  \def\subjectname      {Oggetto:}%
+  \def\registeredname   {Raccomandata}%
+  \def\registeredRRname {\registeredname~A.R.}%
+  \def\andccname        {e~p.~c.}%
+  \def\ccname           {P.~c.:}%
+  \def\enclname         {Allegati:}%
+  \def\PSname           {P.S.:}%
+  \def\headtoname       {A:}%
+  \def\lettername       {Lettera}%
+}
+\def\@cdpbabel@artlet@names{%
+  \def\contentsname     {Sommario}%
+  \def\listfigurename   {Indice delle figure}%
+  \def\listtablename    {Indice delle tabelle}%
+  \def\refname          {Testi citati}%
+%%  \def\indexname        {Indice analitico}%
+%%  \def\figurename       {Figura}%
+%%  \def\tablename        {Tabella}%
+}
+%</lang-it>
+%    \end{macrocode}
+%
+% \section{End of input}
+%
+%    The usual "\endinput" which prevents the \DS\ program from putting
+%    garbage into the generated files.
+%    \begin{macrocode}
+\endinput
+%    \end{macrocode}
+%
+% \Finale
+%
diff --git a/macros/latex/contrib/cdpbundl/cdpbundl.ins b/macros/latex/contrib/cdpbundl/cdpbundl.ins
new file mode 100644
index 0000000000..40cff0bd27
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/cdpbundl.ins
@@ -0,0 +1,193 @@
+%
+% This is file `cdpbundl.ins'.
+%
+% This file is part of a work named "C.D.P. Bundle".
+%
+% Copyright (C) 1999-2018 by Gustavo MEZZETTI
+%                           <gustavo.mezzetti@istruzione.it>.
+%
+% The C.D.P. Bundle may be distributed and/or modified under the
+% conditions of the LaTeX Project Public License, either version 1.3
+% of this license or (at your option) any later version.
+% The latest version of this license is in
+%   http://www.latex-project.org/lppl.txt
+% and version 1.3 or later is part of all distributions of LaTeX
+% version 2005/12/01 or later.
+%
+% The C.D.P. Bundle has the LPPL maintenance status
+%   "author-maintained".
+%
+% The file `manifest.txt' that comes along with this file specifies
+% what the C.D.P. Bundle consists of; more precisely, it explains how
+% the locutions "Work" and "Compiled Work", used in the LaTeX Project
+% Public License, are to be interpreted in the case of this work.
+%
+% Note that the distribution of this file alone is "distribution of
+% only part of the Work" in the sense of the LaTeX Project Public
+% License, and should be avoided.
+%
+% February 8, 2018 (vers. 0.36d)
+%
+\input docstrip
+
+\def\filename{cdpbundl.dtx}
+
+\newif\ifWritingToDirectoryOfTDS
+\WritingToDirectoryOfTDSfalse
+
+\edef\WriteToDir{\WriteToDir}
+\def\TryToUseMyDir{%
+	\usedir{tex/latex/cdpbundl}
+	\ifx \destdir\WriteToDir \else
+		\WritingToDirectoryOfTDStrue
+	\fi
+}
+\def\Y{Y}
+
+
+
+\Msg{----------------------------------------------------------------}
+\Msg{}
+\Msg{Unpacking the C.D.P. Bundle.}
+\Msg{}
+\Msg{The macro files contained in the C.D.P. Bundle are now standard,}
+\Msg{so it now makes sense to try to install the generated files into}
+\Msg{their own TeX directory, using the \string\usedir\space facility of DocStrip;}
+\Msg{if that fails, they will be just saved in the current directory.}
+\Msg{In this case, in order to finish the installation, you will have}
+\Msg{to move them into a directory where LaTeX can find them: see the}
+\Msg{documentation specific to your TeX implementation to learn where}
+\Msg{such directories are located on your system.}
+\Msg{}
+
+\catcode`\@ = 11
+
+\ifx \usedir\alt@usedir
+
+\Msg{On your system, the name of the installation directory should be}
+\Msg{}
+\Msg{\space\space\space\space\showdirectory{tex/latex/cdpbundl}}
+\Msg{}
+\Msg{Please make sure that the above directory exists on your system,}
+\Msg{and that you have permission to create or overwrite files in it;}
+\Msg{if so, you may choose to put the generated files directly there.}
+\Msg{}
+\Msg{----------------------------------------------------------------}
+\Msg{}
+\Msg{Put files directly in suggested directory}
+\Msg{\space\space\space\space\showdirectory{tex/latex/cdpbundl}}
+\Ask\answer{or not? [y/n]}
+
+\ifx \answer\yes
+	\TryToUseMyDir
+\else \ifx \answer\y
+	\TryToUseMyDir
+\else \ifx \answer\Y
+	\TryToUseMyDir
+\fi \fi \fi
+
+\else % of \ifx \usedir\alt@usedir
+
+\Msg{It seems that the configuration of your system does not allow us}
+\Msg{to use the \string\usedir\space facility: writing files to current directory.}
+
+\fi % of \ifx \usedir\alt@usedir
+
+\Msg{}
+
+\ifWritingToDirectoryOfTDS
+
+\Msg{Trying to install files directly in the proposed directory.}
+\Msg{}
+
+\else
+
+\Msg{Either you chose NOT to install files in the proposed directory,}
+\Msg{or, despite your choice, your system is not configured to permit}
+\Msg{you to do so. \space Therefore all files will be placed in the current}
+\Msg{directory and you will have to move them to a suitable directory}
+\Msg{by hand. \space At the end of this run, you will be presented with the}
+\Msg{complete list of the files you need to move.}
+\Msg{}
+\Ask\answer{Press \space <return> \space to continue
+	(your \string\answer\space will be ignored).}
+
+\fi
+
+\preamble
+
+This is a generated file.
+It is part of a work named "C.D.P. Bundle".
+
+Copyright (C) 1999-2018 by Gustavo MEZZETTI
+                          <gustavo.mezzetti@istruzione.it>.
+
+The C.D.P. Bundle may be distributed and/or modified under the
+conditions of the LaTeX Project Public License, either version 1.3
+of this license or (at your option) any later version.
+The latest version of this license is in
+  http://www.latex-project.org/lppl.txt
+and version 1.3 or later is part of all distributions of LaTeX
+version 2005/12/01 or later.
+
+The C.D.P. Bundle has the LPPL maintenance status
+  "author-maintained".
+
+The file `manifest.txt' that comes along with this file specifies
+what the C.D.P. Bundle consists of; more precisely, it explains how
+the locutions "Work" and "Compiled Work", used in the LaTeX Project
+Public License, are to be interpreted in the case of this work.
+
+Note that the distribution of this file alone is "distribution of
+only part of the Work" in the sense of the LaTeX Project Public
+License, and should be avoided.
+
+February 8, 2018 (vers. 0.36d)
+
+\endpreamble
+
+\askonceonly
+
+\generate{
+	\file{letteracdp.cls}      {\from{\filename}{letter}}
+	\file{articoletteracdp.cls}{\from{\filename}{artico}}
+	\file{cdpaddon.sty}        {\from{\filename}{addon}}
+	\file{cdpbabel.sty}        {\from{\filename}{babel}}
+	\file{cdpshues-example.def}{\from{\filename}{example}}
+	\file{epson-stylus-740.def}{\from{\filename}{epson}}
+	\file{hp-laserjet-4500.def}{\from{\filename}{hplj}}
+	\file{cdpshues.cfg}        {\from{\filename}{config}}
+	\file{cdpnamesenglish.ldf} {\from{\filename}{lang-en}}
+	\file{cdpnamesitalian.ldf} {\from{\filename}{lang-it}}
+}
+
+\Msg{}
+
+\ifWritingToDirectoryOfTDS
+
+\Msg{Installation finished. \space Check that the proposed directory}
+\Msg{\space\space\space\space\showdirectory{tex/latex/cdpbundl}}
+\Msg{has been correctly updated.}
+
+\else
+
+\Msg{To finish the installation, please move the following files into}
+\Msg{a directory where LaTeX looks for inputs files:}
+\Msg{}
+\Msg{\space\space\space\space articoletteracdp.cls}
+\Msg{\space\space\space\space cdpaddon.sty}
+\Msg{\space\space\space\space cdpbabel.sty}
+\Msg{\space\space\space\space cdpnamesenglish.ldf}
+\Msg{\space\space\space\space cdpnamesitalian.ldf}
+\Msg{\space\space\space\space cdpshues-example.def}
+\Msg{\space\space\space\space cdpshues.cfg}
+\Msg{\space\space\space\space epson-stylus-740.def}
+\Msg{\space\space\space\space hp-laserjet-4500.def}
+\Msg{\space\space\space\space letteracdp.cls}
+
+\fi
+
+\Msg{}
+\Msg{Happy TeXing!}
+
+\endbatchfile
diff --git a/macros/latex/contrib/cdpbundl/manifest.txt b/macros/latex/contrib/cdpbundl/manifest.txt
new file mode 100644
index 0000000000..8983828df0
--- /dev/null
+++ b/macros/latex/contrib/cdpbundl/manifest.txt
@@ -0,0 +1,108 @@
+
+This is file `manifest.txt'.
+
+This file is part of a work named "C.D.P. Bundle".
+
+Copyright (C) 1999-2018 by Gustavo MEZZETTI
+                          <gustavo.mezzetti@istruzione.it>.
+
+The C.D.P. Bundle may be distributed and/or modified under the
+conditions of the LaTeX Project Public License, either version 1.3
+of this license or (at your option) any later version.
+The latest version of this license is in
+  http://www.latex-project.org/lppl.txt
+and version 1.3 or later is part of all distributions of LaTeX
+version 2005/12/01 or later.
+
+The C.D.P. Bundle has the LPPL maintenance status
+  "author-maintained".
+
+This file specifies what the C.D.P. Bundle consists of; more
+precisely, it explains how the locutions "Work" and "Compiled Work",
+used in the LaTeX Project Public License, are to be interpreted
+in the case of this work.
+
+February 8, 2018 (vers. 0.36d)
+
+
+
+MEANING OF THE TERM "Work"
+==========================
+
+In the case of the C.D.P. Bundle, the "Work" is the collection of the 
+following 4 files:
+
+00readme.txt    --  start by reading this file
+manifest.txt    --  the file you are reading now
+cdpbundl.dtx    --  main source file
+cdpbundl.ins    --  installation script
+
+If you have received the 4 files listed above, you possess an integral copy 
+of the C.D.P. Bundle.
+
+
+
+MEANING OF THE TERM "Compiled Work"
+===================================
+
+In the case of the C.D.P. Bundle, a "Compiled Work" is the collection of:
+
+a) the following 2 files that are also part of the "Work" (see above):
+
+00readme.txt
+manifest.txt
+
+AND
+b) the following 11 files:
+
+letteracdp.cls          --  the letteracdp LaTeX document class
+articoletteracdp.cls    --  the articoletteracdp LaTeX document class
+cdpaddon.sty            --  the cdpaddon LaTeX package
+cdpbabel.sty            --  the cdpbabel LaTeX package
+cdpnamesenglish.ldf     --  language-dependent definitions of the captions
+cdpnamesitalian.ldf     /
+cdpshues-example.def    --  prototype color definition file
+epson-stylus-740.def    --  other example color definition files
+hp-laserjet-4500.def    /
+cdpshues.cfg            --  configuration file for the cdpaddon package
+cdpbundl.dvi            --  full documentation in DVI format
+
+You may, at your option, substitute the file `cdpbundl.dvi' with either 
+one (or both) of the following two files:
+
+cdpbundl.pdf            --  full documentation in PDF
+cdpbundl-doc.pdf        --  overview of the C.D.P. Bundle (PDF)
+
+but at least one among the files `cdpbundl.dvi', `cdpbundl.pdf', and 
+`cdpbundl-doc.pdf' must be included in a "Compiled Work" that you intend 
+to distribute.  The file `cdpbundl.pdf' is obtained by submitting to the 
+program pdflatex the file `cdpbundl.dtx', following the same steps as 
+those explained in `00readme.txt' under the title "How to generate the 
+documentation".
+
+
+
+ANCILLARY FILES
+===============
+
+The package of files distributed through the Comprehensive TeX Archive 
+Network (CTAN) includes also the following five files:
+
+README              --  guide to directory contents
+cdpbundl-doc.pdf    --  overview of the C.D.P. Bundle (PDF)
+cdp-ver-0-36.pdf    --  instructions specific to version 0.36 (PDF)
+cdp-ver-0-36.tex    --  LaTeX source of the preceding item
+Makefile            --  Makefile to generate code and/or documentation
+
+These five files are included only for convenience's sake and are _not_ a 
+required part of the C.D.P. Bundle (of course you may, if you wish, include 
+them in your distribution too).
+
+
+
+COMMENT
+=======
+
+Please remember that, in order to distribute a LPPL-compliant copy of the 
+C.D.P. Bundle, it suffices to distribute only the 4 files that constitute 
+the "Work".