is-bst, follow separate package on CTAN; remove nonfree astron-derived human*.bst

git-svn-id: svn://tug.org/texlive/trunk@52623 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 2665 insertions, 0 deletions

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@@ -0,0 +1,2665 @@
+% /u/sy/beebe/tex/bib/merge/xbtxbst.doc, Thu Sep 12 10:19:13 1991
+% Edit by Nelson H. F. Beebe <beebe@magna.math.utah.edu>
+% /u/sy/beebe/tex/bib/merge/xbtxbst.doc, Wed Oct 17 08:27:24 1990
+% Edit by Nelson H.F. Beebe <beebe@sandy.math.utah.edu>
+
+% NB: Important convention: comment lines beginning with 2 (or
+%     more) percents are to be preserved in the derived style
+%     files.   Comment lines beginning with only 1 percent can be
+%     discarded (and are, if the derived files are produced with
+%     the UNIX Makefile that accompanies this file.)
+
+%% =====================================================================
+%%  @BibTeX-style-file{
+%%      author          = "Nelson H. F. Beebe",
+%%      version         = "1.02",
+%%      date            = "12 September 1991",
+%%      filename        = "xbtxbst.doc",
+%%      address         = "Center for Scientific Computing
+%%                         Department of Mathematics
+%%                         South Physics Building
+%%                         University of Utah
+%%                         Salt Lake City, UT 84112
+%%                         USA
+%%                         Tel: (801) 581-5254",
+%%      checksum        = "50938 2665 11236 78415",
+%%      email           = "beebe@math.utah.edu (Internet)",
+%%      codetable       = "ISO/ASCII",
+%%      keywords        = "BibTeX, style, bibliography",
+%%      supported       = "yes",
+%%      docstring       = "This file is a modification of the standard
+%%                         BibTeX btxbst.doc file, or is a .bst file
+%%                         derived from that modification.  It contains
+%%                         added support for ISBN and ISSN fields, as
+%%                         well as for the PERIODICAL entry.  The UNIX C
+%%                         preprocessor can be used to extract the
+%%                         extensions of the standard styles, as
+%%                         follows:
+%%
+%%                         cpp -P -DPLAIN xbtxbst.doc is-plain.txt
+%%                         cpp -P -DUNSRT xbtxbst.doc is-unsrt.txt
+%%                         cpp -P -DALPHA xbtxbst.doc is-alpha.txt
+%%                         cpp -P -DABBRV xbtxbst.doc is-abbrv.txt
+%%
+%%                         If desired, a sed script can be used to
+%%                         eliminate non-essential comments (this
+%%                         reduces the file size by 2/3); a command
+%%                         filter step like
+%%                                 sed -e '/^%$/d' -e '/^%[^%].*$/d'
+%%                         will accomplish that job.
+%%
+%%                         The checksum field above contains a CRC-16
+%%                         checksum as the first value, followed by the
+%%                         equivalent of the standard UNIX wc (word
+%%                         count) utility output of lines, words, and
+%%                         characters.  This is produced by Robert
+%%                         Solovay's checksum utility."
+%%      }
+%% =====================================================================
+%% Revision history (reverse time order):
+%% 1.02 [12-Sep-1991]
+%%      Merge in Barbara N. Beeton's suggestion for hyphen-less
+%%      line breaks around volume(number):page.
+%% 1.01 [10-Sep-1991]
+%%      Update file comment header and use Solovay checksum program.
+%% 1.00 [17-Oct-1990]
+%%      Original version merging hand-edits of is-xxx.bst files into
+%%      this master file, xbtxbst.doc.
+
+% In the following, only essential changes have been applied; the
+% documentation immediately below referring to the use of cpp on
+% btxbst.doc has not been altered.  See the docstring entry above
+% for current information.
+
+%% BibTeX `plain' family
+%%       version 0.99b for BibTeX versions 0.99a or later, LaTeX version 2.09.
+%%       Copyright (C) 1985, all rights reserved.
+%%       Copying of this file is authorized only if either
+%%       (1) you make absolutely no changes to your copy, including name, or
+%%       (2) if you do make changes, you name it something other than
+%%       btxbst.doc, plain.bst, unsrt.bst, alpha.bst, and abbrv.bst.
+%%       This restriction helps ensure that all standard styles are identical.
+%%       The file btxbst.doc has the documentation for this style.
+%
+% Please notify Oren Patashnik (PATASHNIK@SCORE.STANFORD.EDU) of any bugs in
+% these standard styles or in this documentation file.
+%
+% This is file btxbxt.doc; it helps document bibliography styles,
+% and is also a template file that you can use to make
+% several different style files, if you have access to a C preprocessor.
+% For example, the standard styles were made by doing something like
+%       cpp -P -DPLAIN btxbst.doc plain.txt
+%       cpp -P -DUNSRT btxbst.doc unsrt.txt
+%       cpp -P -DALPHA btxbst.doc alpha.txt
+%       cpp -P -DABBRV btxbst.doc abbrv.txt
+% and then renaming after removing unwanted comments and blank lines.
+% If you don't have access,
+% you can edit this file by hand to imitate the preprocessor,
+% with the following explanation of the C preprocessor constructs used here.
+%
+% The output of the preprocessor is the same as the input, except that certain
+% lines will be excluded (and some blank lines will be added).  The sequence
+%       #if VAR
+%           lines to be included when VAR is not zero
+%       #else
+%           lines to be included when VAR is zero
+%       #endif
+% (with the #-signs appearing in column 1) means that one set or the other of
+% the lines are to be included depending on the value of VAR.
+% The #else part is optional.  Comments can be added after #else and #endif.
+% Variables can be set by
+%       #define VAR value
+% and one can also use #ifdef VAR to see if VAR has any value, and #ifndef
+% to see if it has none.
+% Another #if form used in this file is #if !VAR, which includes the lines
+% after the #if only if VAR is zero.
+%
+% Convention: Use all uppercase identifiers for these preprocessor variables
+% so you can spot them easily
+%
+% The command line to the preprocessor should define one of PLAIN, UNSRT, ALPHA
+% or ABBRV (though PLAIN will be used by default if none is given),
+% and the following lines will set various boolean variables to control the
+% various lines that are chosen from the rest of the file.
+% Each boolean variable should be set true (1) or false (0) in each style.
+% Here are the current variables, and their meanings:
+%       LAB_ALPH:       an alphabetic label is used (if false then a numeric
+%                           label is used)
+%       SORTED:         the entries should be sorted by label (if nonnumeric)
+%                           and other info, like authors (if false, then
+%                           entries remain in order of occurrence)
+%       NAME_FULL:      the authors, editors, etc., get the full names as
+%                           given in the bibliography file (if false, the first
+%                           names become initials)
+%       ATIT_LOWER:     titles of non-"books" (e.g., articles) should be
+%                           converted to lower-case, except the first letter or
+%                           first letter after a colon
+%                           (if false then they appear as in the database)
+%       MONTH_FULL:     months are spelled out in full (if false, then
+%                           they're abbreviated)
+%       JOUR_FULL:      macro journal names are spelled out in full
+%                           (if false then they are abbreviated, currently
+%                           as they appear in ACM publications)
+#ifndef UNSRT
+#   ifndef ALPHA
+#       ifndef ABBRV
+#           define PLAIN 1
+#       endif
+#   endif
+#endif
+#ifdef PLAIN
+% plain style (sorted numbers)
+#   define LAB_ALPH 0
+#   define SORTED 1
+#   define NAME_FULL 1
+#   define ATIT_LOWER 1
+#   define MONTH_FULL 1
+#   define JOUR_FULL 1
+#endif
+#ifdef UNSRT
+% unsrt style (unsorted numbers)
+#   define LAB_ALPH 0
+#   define SORTED 0
+#   define NAME_FULL 1
+#   define ATIT_LOWER 1
+#   define MONTH_FULL 1
+#   define JOUR_FULL 1
+#endif
+#ifdef ALPHA
+% alpha style (sorted short alphabetics)
+#   define LAB_ALPH 1
+#   define SORTED 1
+#   define NAME_FULL 1
+#   define ATIT_LOWER 1
+#   define MONTH_FULL 1
+#   define JOUR_FULL 1
+#endif
+#ifdef ABBRV
+% abbrv style (sorted numbers, with abbreviations)
+#   define LAB_ALPH 0
+#   define SORTED 1
+#   define NAME_FULL 0
+#   define ATIT_LOWER 1
+#   define MONTH_FULL 0
+#   define JOUR_FULL 0
+#endif
+%
+%   Entry formatting: Similar to that recommended by Mary-Claire van Leunen
+%       in "A Handbook for Scholars".  Book-like titles are italicized
+%       (emphasized) and non-book titles are converted to sentence
+%       capitilization (and not enclosed in quotes).
+%       This file outputs a \newblock between major blocks of an entry
+%       (the name \newblock is analogous to the names \newline and \newpage)
+%       so that the user can obtain an "open" format, which has a line break
+%       before each block and lines after the first are indented within blocks,
+%       by giving the optional \documentstyle argument `openbib';
+%       The default is the "closed" format---blocks runs together.
+%
+%   Citation alphabetic label format:
+%               [Knu73] for single author (or editor or key)
+%               [AHU83] (first letters of last names) for multiple authors
+%
+%   Citation label numberic format:
+%               [number]
+%
+%   Reference list ordering for sorted, alphabetic lables:
+%               alphabetical by citation label, then by author(s) or whatever
+%               passes for author in the absence of one, then by year,
+%               then title
+%
+%   Reference list ordering for sorted, numeric lables:
+%               alphabetical by author(s) or whatever passes
+%               for author in the absence of one, then by year, then title
+%
+%   Reference list ordering for unsorted:
+%               by the order cited in the text
+%
+%   History
+%   12/16/84    (HWT)   Original `plain' version, by Howard Trickey.
+%   12/23/84    (LL)    Some comments made by Leslie Lamport.
+%    2/16/85    (OP)    Changes based on LL's comments, Oren Patashnik.
+%    2/17/85    (HWT)   Template file and other standard styles made.
+%    3/28/85    (OP)    First release, version 0.98b for BibTeX 0.98f.
+%    5/ 9/85    (OP)    Version 0.98c for BibTeX 0.98i:
+%                       fixed Theoretical Computer Science macro name;
+%                       fixed the format.vol.num.pages function.
+%    1/24/88    (OP)    Version 0.99a for BibTeX 0.99a, main changes:
+%                       assignment operator (:=) arguments reversed;
+%                       the preamble$ function outputs the database PREAMBLE;
+%                       entry.max$ and global.max$ (built-in) variables replace
+%                       entry.string.max and global.string.max functions;
+%                       alphabetizing by year then title, not just title;
+%                       many unnecessary ties removed; \it ==> \em;
+%                       the `alpha' style uses a superscripted `+' instead of a
+%                       `*' for unnamed names in constructing the label;
+%                       the `abbrv' style now uses "Mar." and "Sept.";
+%                       the functions calc.label and presort now look at just
+%                       the fields they're supposed to;
+%                       BOOKLET, MASTERSTHESIS, TECHREPORT use nonbook titles;
+%                       INBOOK and INCOLLECTION take an optional type (e.g.
+%                       type = "Section"), overriding the default "chapter";
+%                       BOOK, INBOOK, INCOLLECTION, and PROCEEDINGS now allow
+%                       either volume or number, not just volume;
+%                       INCOLLECTION now allows an edition and series field;
+%                       PROCEEDINGS and INPROCEEDINGS now use the address field
+%                       to tell where a conference was held;
+%                       INPROCEEDINGS and PROCEEDINGS now allow either volume
+%                       or number, and also a series field;
+%                       MASTERSTHESIS and PHDTHESIS accept types other than
+%                       "Master's thesis" and "PhD thesis";
+%                       UNPUBLISHED now outputs, in one block, note then date;
+%                       MANUAL now prints out the organization in
+%                       the first block if the author field is empty;
+%                       MISC can't be empty---it requires some optional field.
+%    3/23/88    (OP)    Version 0.99b for BibTeX 0.99c---changed the three
+%                       erroneous occurrences of `cite ' to `cite$ '; this
+%                       change didn't affect the four standard styles, so the
+%                       0.99a versions of those styles are still current.
+%
+% The ENTRY declaration
+%   Like Scribe's (according to pages 231-2 of the April '84 edition),
+%   but no fullauthor or editors fields because BibTeX does name handling.
+%   The annote field is commented out here because this family doesn't
+%   include an annotated bibliography style.  And in addition to the fields
+%   listed here, BibTeX has a built-in crossref field, explained later.
+
+ENTRY
+% Fields:
+  { address
+%           Usually the address of a publisher or other type of organization.
+%           Put information in this field only if it helps the reader find the
+%           thing---for example you should omit the address of a major
+%           publisher entirely.  For a PROCEEDINGS or an INPROCEEDINGS,
+%           however, it's the address of the conference; for those two entry
+%           types, include the publisher's or organization's address, if
+%           necessary, in the publisher or organization field.
+%    annote
+%           Long annotation---for annotated bibliographies (begins sentence).
+    author
+%           Name(s) of author(s), in BibTeX name format.
+    booktitle
+%           Book title when the thing being referenced isn't the whole book.
+%           For book entries, the title field should be used instead.
+    chapter
+%           Chapter (or section or whatever) number.
+    edition
+%           Edition of a book---should be an ordinal (e.g., "Second").
+    editor
+%           Name(s) of editor(s), in BibTeX name format.
+%           If there is also an author field, then the editor field should be
+%           for the book or collection that the work appears in.
+    howpublished
+%            How something strange has been published (begins sentence).
+    institution
+%           Sponsoring institution of a technical report.
+    isbn
+%           ISBN book number (a 10-digit number with optional
+%           embedded spaces or hyphens, where a `digit' is one of
+%           0123456789X).
+    issn
+%           ISSN serial publication number (an 8-digit number with optional
+%           embedded spaces or hyphens, where a `digit' is one of
+%           0123456789X).
+    journal
+%           Journal name (macros are provided for many).
+    key
+%           Alphabetizing, labeling, and cross-referencing key
+%           (needed when an entry has no author or editor).
+    month
+%           Month (macros are provided).
+    note
+%           To help the reader find a reference (begins sentence).
+    number
+%           Number of a journal or technical report, or of a work in a series.
+    organization
+%           Organization sponsoring a conference (or publishing a manual); if
+%           the editor (or author) is empty, and if the organization produces
+%           an awkward label or cross reference, you should put appropriately
+%           condensed organization information in the key field as well.
+    pages
+%           Page number or numbers (use `--' to separate a range, use `+'
+%           to indicate pages following that don't form a simple range).
+    publisher
+%           Publisher name.
+    school
+%           School name (for theses).
+    series
+%           The name of a series or set of books.
+%           An individual book will will also have it's own title.
+    title
+%           The title of the thing you're referred to.
+    type
+%           Type of a Techreport (e.g., "Research Note") to be used instead of
+%           the default "Technical Report"; or, similarly, the type of a
+%           thesis; or of a part of a book.
+    volume
+%           The volume number of a journal or multivolume work.
+    year
+%           The year should contain only numerals (technically, it should end
+%           with four numerals, after purification; doesn't a begin sentence).
+  }
+% There are no integer entry variables
+  {}
+% These string entry variables are used to form the citation label.
+% In a storage pinch, sort.label can be easily computed on the fly.
+#if LAB_ALPH
+#if SORTED
+  { label extra.label sort.label }
+#else !SORTED
+% It doesn't seem like a good idea to use an order-of-citation
+% reference list when using alphabetic labels, but when this happens
+% we do things a little differently
+  { label }
+#endif SORTED
+#else !LAB_ALPH
+  { label }
+#endif LAB_ALPH
+
+% Each entry function starts by calling output.bibitem, to write the
+% \bibitem and its arguments to the .BBL file.  Then the various fields
+% are formatted and printed by output or output.check.  Those functions
+% handle the writing of separators (commas, periods, \newblock's),
+% taking care not to do so when they are passed a null string.
+% Finally, fin.entry is called to add the final period and finish the
+% entry.
+%
+% A bibliographic reference is formatted into a number of `blocks':
+% in the open format, a block begins on a new line and subsequent
+% lines of the block are indented.  A block may contain more than
+% one sentence (well, not a grammatical sentence, but something to
+% be ended with a sentence ending period).  The entry functions should
+% call new.block whenever a block other than the first is about to be
+% started.  They should call new.sentence whenever a new sentence is
+% to be started.  The output functions will ensure that if two
+% new.sentence's occur without any non-null string being output between
+% them then there won't be two periods output.  Similarly for two
+% successive new.block's.
+%
+% The output routines don't write their argument immediately.
+% Instead, by convention, that argument is saved on the stack to be
+% output next time (when we'll know what separator needs to come
+% after it).  Meanwhile, the output routine has to pop the pending
+% output off the stack, append any needed separator, and write it.
+%
+% To tell which separator is needed, we maintain an output.state.
+% It will be one of these values:
+%       before.all              just after the \bibitem
+%       mid.sentence            in the middle of a sentence: comma needed
+%                                       if more sentence is output
+%       after.sentence          just after a sentence: period needed
+%       after.block             just after a block (and sentence):
+%                                       period and \newblock needed.
+% Note: These styles don't use after.sentence
+%
+% VAR: output.state : INTEGER           -- state variable for output
+%
+% The output.nonnull function saves its argument (assumed to be nonnull)
+% on the stack, and writes the old saved value followed by any needed
+% separator.  The ordering of the tests is decreasing frequency of
+% occurrence.
+%
+% output.nonnull(s) ==
+%  BEGIN
+%       s := argument on stack
+%       if output.state = mid.sentence then
+%           write$(pop() * ", ")
+%                 -- "pop" isn't a function: just use stack top
+%       else
+%           if output.state = after.block then
+%               write$(add.period$(pop()))
+%               newline$
+%               write$("\newblock ")
+%           else
+%               if output.state = before.all then
+%                   write$(pop())
+%               else        -- output.state should be after.sentence
+%                   write$(add.period$(pop()) * " ")
+%               fi
+%           fi
+%           output.state := mid.sentence
+%       fi
+%       push s on stack
+%  END
+%
+% The output function calls output.nonnull if its argument is non-empty;
+% its argument may be a missing field (thus, not necessarily a string)
+%
+% output(s) ==
+%  BEGIN
+%       if not empty$(s) then output.nonnull(s)
+%       fi
+%  END
+%
+% The output.check function is the same as the output function except that, if
+% necessary, output.check warns the user that the t field shouldn't be empty
+% (this is because it probably won't be a good reference without the field;
+% the entry functions try to make the formatting look reasonable even when
+% such fields are empty).
+%
+% output.check(s,t) ==
+%  BEGIN
+%       if empty$(s) then
+%           warning$("empty " * t * " in " * cite$)
+%       else output.nonnull(s)
+%       fi
+%  END
+%
+% The output.bibitem function writes the \bibitem for the current entry
+% (the label should already have been set up), and sets up the separator
+% state for the output functions.  And, it leaves a string on the stack
+% as per the output convention.
+%
+% output.bibitem ==
+%  BEGIN
+%       newline$
+%       write$("\bibitem[")     % for alphabetic labels,
+%       write$(label)           % these three lines
+%       write$("]{")            % are used
+%       write$("\bibitem{")             % this line for numeric labels
+%       write$(cite$)
+%       write$("}")
+%       push "" on stack
+%       output.state := before.all
+%  END
+%
+% The fin.entry function finishes off an entry by adding a period to the
+% string remaining on the stack.  If the state is still before.all
+% then nothing was produced for this entry, so the result will look bad,
+% but the user deserves it. (We don't omit the whole entry because the
+% entry was cited, and a bibitem is needed to define the citation label.)
+%
+% fin.entry ==
+%  BEGIN
+%       write$(add.period$(pop()))
+%       newline$
+%  END
+%
+% The new.block function prepares for a new block to be output, and
+% new.sentence prepares for a new sentence.
+%
+% new.block ==
+%  BEGIN
+%       if output.state <> before.all then
+%           output.state := after.block
+%       fi
+%  END
+%
+% new.sentence ==
+%  BEGIN
+%       if output.state <> after.block then
+%           if output.state <> before.all then
+%               output.state :=  after.sentence
+%           fi
+%       fi
+%  END
+%
+
+INTEGERS { output.state before.all mid.sentence after.sentence after.block }
+
+FUNCTION {init.state.consts}
+{ #0 'before.all :=
+  #1 'mid.sentence :=
+  #2 'after.sentence :=
+  #3 'after.block :=
+}
+
+% the variables s and t are temporary string holders
+
+STRINGS { s t }
+
+FUNCTION {output.nonnull}
+{ 's :=
+  output.state mid.sentence =
+    { ", " * write$ }
+    { output.state after.block =
+        { add.period$ write$
+          newline$
+          "\newblock " write$
+        }
+        { output.state before.all =
+            'write$
+            { add.period$ " " * write$ }
+          if$
+        }
+      if$
+      mid.sentence 'output.state :=
+    }
+  if$
+  s
+}
+
+FUNCTION {output}
+{ duplicate$ empty$
+    'pop$
+    'output.nonnull
+  if$
+}
+
+FUNCTION {output.check}
+{ 't :=
+  duplicate$ empty$
+    { pop$ "empty " t * " in " * cite$ * warning$ }
+    'output.nonnull
+  if$
+}
+
+FUNCTION {output.bibitem}
+{ newline$
+#if LAB_ALPH
+  "\bibitem[" write$
+  label write$
+  "]{" write$
+#else
+  "\bibitem{" write$
+#endif LAB_ALPH
+  cite$ write$
+  "}" write$
+  newline$
+  ""
+  before.all 'output.state :=
+}
+
+% This function finishes all entries.
+
+FUNCTION {fin.entry}
+{ add.period$
+  write$
+  newline$
+}
+
+FUNCTION {new.block}
+{ output.state before.all =
+    'skip$
+    { after.block 'output.state := }
+  if$
+}
+
+FUNCTION {new.sentence}
+{ output.state after.block =
+    'skip$
+    { output.state before.all =
+        'skip$
+        { after.sentence 'output.state := }
+      if$
+    }
+  if$
+}
+
+% These three functions pop one or two (integer) arguments from the stack
+% and push a single one, either 0 or 1.
+% The 'skip$ in the `and' and `or' functions are used because
+% the corresponding if$ would be idempotent
+
+FUNCTION {not}
+{   { #0 }
+    { #1 }
+  if$
+}
+
+FUNCTION {and}
+{   'skip$
+    { pop$ #0 }
+  if$
+}
+
+FUNCTION {or}
+{   { pop$ #1 }
+    'skip$
+  if$
+}
+
+% Sometimes we begin a new block only if the block will be big enough.  The
+% new.block.checka function issues a new.block if its argument is nonempty;
+% new.block.checkb does the same if either of its TWO arguments is nonempty.
+
+FUNCTION {new.block.checka}
+{ empty$
+    'skip$
+    'new.block
+  if$
+}
+
+FUNCTION {new.block.checkb}
+{ empty$
+  swap$ empty$
+  and
+    'skip$
+    'new.block
+  if$
+}
+
+% The new.sentence.check functions are analogous.
+
+FUNCTION {new.sentence.checka}
+{ empty$
+    'skip$
+    'new.sentence
+  if$
+}
+
+FUNCTION {new.sentence.checkb}
+{ empty$
+  swap$ empty$
+  and
+    'skip$
+    'new.sentence
+  if$
+}
+
+% Here are some functions for formatting chunks of an entry.
+% By convention they either produce a string that can be followed by
+% a comma or period (using add.period$, so it is OK to end in a period),
+% or they produce the null string.
+%
+% A useful utility is the field.or.null function, which checks if the
+% argument is the result of pushing a `missing' field (one for which no
+% assignment was made when the current entry was read in from the database)
+% or the result of pushing a string having no non-white-space characters.
+% It returns the null string if so, otherwise it returns the field string.
+% Its main (but not only) purpose is to guarantee that what's left on the
+% stack is a string rather than a missing field.
+%
+% field.or.null(s) ==
+%  BEGIN
+%       if empty$(s) then return ""
+%       else return s
+%  END
+%
+% Another helper function is emphasize, which returns the argument emphazised,
+% if that is non-empty, otherwise it returns the null string.  Italic
+% corrections aren't used, so this function should be used when punctation
+% will follow the result.
+%
+% emphasize(s) ==
+%  BEGIN
+%       if empty$(s) then return ""
+%       else return "{\em " * s * "}"
+%
+% The format.names function formats the argument (which should be in
+% BibTeX name format) into "First Von Last, Junior", separated by commas
+% and with an "and" before the last (but ending with "et~al." if the last
+% of multiple authors is "others").  This function's argument should always
+% contain at least one name.
+%
+% VAR: nameptr, namesleft, numnames: INTEGER
+% pseudoVAR: nameresult: STRING         (it's what's accumulated on the stack)
+%
+% format.names(s) ==
+%  BEGIN
+%       nameptr := 1
+%       numnames := num.names$(s)
+%       namesleft := numnames
+%       while namesleft > 0
+%         do
+%                               % for full names:
+%           t := format.name$(s, nameptr, "{ff~}{vv~}{ll}{, jj}")
+%                               % for abbreviated first names:
+%           t := format.name$(s, nameptr, "{f.~}{vv~}{ll}{, jj}")
+%           if nameptr > 1 then
+%               if namesleft > 1 then nameresult := nameresult * ", " * t
+%               else if numnames > 2
+%                      then nameresult := nameresult * ","
+%                    fi
+%                    if t = "others"
+%                      then nameresult := nameresult * " et~al."
+%                      else nameresult := nameresult * " and " * t
+%                    fi
+%               fi
+%           else nameresult := t
+%           fi
+%           nameptr := nameptr + 1
+%           namesleft := namesleft - 1
+%         od
+%       return nameresult
+%  END
+%
+% The format.authors function returns the result of format.names(author)
+% if the author is present, or else it returns the null string
+%
+% format.authors ==
+%  BEGIN
+%       if empty$(author) then return ""
+%       else return format.names(author)
+%       fi
+%  END
+%
+% Format.editors is like format.authors, but it uses the editor field,
+% and appends ", editor" or ", editors"
+%
+% format.editors ==
+%  BEGIN
+%       if empty$(editor) then return ""
+%       else
+%           if num.names$(editor) > 1 then
+%               return format.names(editor) * ", editors"
+%           else
+%               return format.names(editor) * ", editor"
+%           fi
+%       fi
+%  END
+%
+% Other formatting functions are similar, so no "comment version" will be
+% given for them.
+%
+% The `pop$' in this function gets rid of the duplicate `empty' value and
+% the `skip$' returns the duplicate field value
+
+FUNCTION {field.or.null}
+{ duplicate$ empty$
+    { pop$ "" }
+    'skip$
+  if$
+}
+
+FUNCTION {emphasize}
+{ duplicate$ empty$
+    { pop$ "" }
+    { "{\em " swap$ * "}" * }
+  if$
+}
+
+INTEGERS { nameptr namesleft numnames }
+
+FUNCTION {format.names}
+{ 's :=
+  #1 'nameptr :=
+  s num.names$ 'numnames :=
+  numnames 'namesleft :=
+    { namesleft #0 > }
+#if NAME_FULL
+    { s nameptr "{ff~}{vv~}{ll}{, jj}" format.name$ 't :=
+#else
+    { s nameptr "{f.~}{vv~}{ll}{, jj}" format.name$ 't :=
+#endif NAME_FULL
+      nameptr #1 >
+        { namesleft #1 >
+            { ", " * t * }
+            { numnames #2 >
+                { "," * }
+                'skip$
+              if$
+              t "others" =
+                { " et~al." * }
+                { " and " * t * }
+              if$
+            }
+          if$
+        }
+        't
+      if$
+      nameptr #1 + 'nameptr :=
+      namesleft #1 - 'namesleft :=
+    }
+  while$
+}
+
+FUNCTION {format.authors}
+{ author empty$
+    { "" }
+    { author format.names }
+  if$
+}
+
+FUNCTION {format.editors}
+{ editor empty$
+    { "" }
+    { editor format.names
+      editor num.names$ #1 >
+        { ", editors" * }
+        { ", editor" * }
+      if$
+    }
+  if$
+}
+
+FUNCTION {format.isbn}
+{ isbn empty$
+    { "" }
+    { new.block "ISBN " isbn * }
+  if$
+}
+
+FUNCTION {format.issn}
+{ issn empty$
+    { "" }
+    { new.block "ISSN " issn * }
+  if$
+}
+
+% The format.title function is used for non-book-like titles.
+% For most styles we convert to lowercase (except for the very first letter,
+% and except for the first one after a colon (followed by whitespace)),
+% and hope the user has brace-surrounded words that need to stay capitilized;
+% for some styles, however, we leave it as it is in the database.
+
+FUNCTION {format.title}
+{ title empty$
+    { "" }
+#if ATIT_LOWER
+    { title "t" change.case$ }
+#else
+    'title
+#endif ATIT_LOWER
+  if$
+}
+
+% By default, BibTeX sets the global integer variable global.max$ to the BibTeX
+% constant glob_str_size, the maximum length of a global string variable.
+% Analogously, BibTeX sets the global integer variable entry.max$ to
+% ent_str_size, the maximum length of an entry string variable.
+% The style designer may change these if necessary (but this is unlikely)
+
+% The n.dashify function makes each single `-' in a string a double `--'
+% if it's not already
+%
+% pseudoVAR: pageresult: STRING         (it's what's accumulated on the stack)
+%
+% n.dashify(s) ==
+%  BEGIN
+%       t := s
+%       pageresult := ""
+%       while (not empty$(t))
+%         do
+%           if (first character of t = "-")
+%             then
+%               if (next character isn't)
+%                 then
+%                   pageresult := pageresult * "--"
+%                   t := t with the "-" removed
+%                 else
+%                   while (first character of t = "-")
+%                     do
+%                       pageresult := pageresult * "-"
+%                       t := t with the "-" removed
+%                     od
+%               fi
+%             else
+%               pageresult := pageresult * the first character
+%               t := t with the first character removed
+%           fi
+%         od
+%       return pageresult
+%  END
+
+FUNCTION {n.dashify}
+{ 't :=
+  ""
+    { t empty$ not }
+    { t #1 #1 substring$ "-" =
+        { t #1 #2 substring$ "--" = not
+            { "--" *
+              t #2 global.max$ substring$ 't :=
+            }
+            {   { t #1 #1 substring$ "-" = }
+                { "-" *
+                  t #2 global.max$ substring$ 't :=
+                }
+              while$
+            }
+          if$
+        }
+        { t #1 #1 substring$ *
+          t #2 global.max$ substring$ 't :=
+        }
+      if$
+    }
+  while$
+}
+
+% The format.date function is for the month and year, but we give a warning if
+% there's an empty year but the month is there, and we return the empty string
+% if they're both empty.
+
+FUNCTION {format.date}
+{ year empty$
+    { month empty$
+        { "" }
+        { "there's a month but no year in " cite$ * warning$
+          month
+        }
+      if$
+    }
+    { month empty$
+        'year
+        { month " " * year * }
+      if$
+    }
+  if$
+}
+
+% The format.btitle is for formatting the title field when it is a book-like
+% entry---the style used here keeps it in uppers-and-lowers and emphasizes it.
+
+FUNCTION {format.btitle}
+{ title emphasize
+}
+
+% For several functions we'll need to connect two strings with a
+% tie (~) if the second one isn't very long (fewer than 3 characters).
+% The tie.or.space.connect function does that.  It concatenates the two
+% strings on top of the stack, along with either a tie or space between
+% them, and puts this concatenation back onto the stack:
+%
+% tie.or.space.connect(str1,str2) ==
+%    BEGIN
+%       if text.length$(str2) < 3
+%         then return the concatenation of str1, "~", and str2
+%         else return the concatenation of str1, " ", and str2
+%    END
+
+FUNCTION {tie.or.space.connect}
+{ duplicate$ text.length$ #3 <
+    { "~" }
+    { " " }
+  if$
+  swap$ * *
+}
+
+% The either.or.check function complains if both fields or an either-or pair
+% are nonempty.
+%
+% either.or.check(t,s) ==
+%  BEGIN
+%       if empty$(s) then
+%           warning$(can't use both " * t * " fields in " * cite$)
+%       fi
+%  END
+
+FUNCTION {either.or.check}
+{ empty$
+    'pop$
+    { "can't use both " swap$ * " fields in " * cite$ * warning$ }
+  if$
+}
+
+% The format.bvolume function is for formatting the volume and perhaps
+% series name of a multivolume work.  If both a volume and a series field
+% are there, we assume the series field is the title of the whole multivolume
+% work (the title field should be the title of the thing being referred to),
+% and we add an "of <series>".  This function is called in mid-sentence.
+
+FUNCTION {format.bvolume}
+{ volume empty$
+    { "" }
+    { "volume" volume tie.or.space.connect
+      series empty$
+        'skip$
+        { " of " * series emphasize * }
+      if$
+      "volume and number" number either.or.check
+    }
+  if$
+}
+
+% The format.number.series function is for formatting the series name
+% and perhaps number of a work in a series.  This function is similar to
+% format.bvolume, although for this one the series must exist (and the
+% volume must not exist).  If the number field is empty we output either
+% the series field unchanged if it exists or else the null string.
+% If both the number and series fields are there we assume the series field
+% gives the name of the whole series (the title field should be the title
+% of the work being one referred to), and we add an "in <series>".
+% We capitilize Number when this function is used at the beginning of a block.
+
+FUNCTION {format.number.series}
+{ volume empty$
+    { number empty$
+        { series field.or.null }
+        { output.state mid.sentence =
+            { "number" }
+            { "Number" }
+          if$
+          number tie.or.space.connect
+          series empty$
+            { "there's a number but no series in " cite$ * warning$ }
+            { " in " * series * }
+          if$
+        }
+      if$
+    }
+    { "" }
+  if$
+}
+
+% The format.edition function appends " edition" to the edition, if present.
+% We lowercase the edition (it should be something like "Third"), because
+% this doesn't start a sentence.
+
+FUNCTION {format.edition}
+{ edition empty$
+    { "" }
+    { output.state mid.sentence =
+        { edition "l" change.case$ " edition" * }
+        { edition "t" change.case$ " edition" * }
+      if$
+    }
+  if$
+}
+
+% The format.pages function is used for formatting a page range in a book
+% (and in rare circumstances, an article).
+%
+% The multi.page.check function examines the page field for a "-" or "," or "+"
+% so that format.pages can use "page" instead of "pages" if none exists.
+% Note: global.max$ here means "take the rest of the string"
+%
+% VAR: multiresult: INTEGER     (actually, a boolean)
+%
+% multi.page.check(s) ==
+%  BEGIN
+%       t := s
+%       multiresult := false
+%       while ((not multiresult) and (not empty$(t)))
+%         do
+%           if (first character of t = "-" or "," or "+")
+%             then multiresult := true
+%             else t := t with the first character removed
+%           fi
+%         od
+%       return multiresult
+%  END
+
+INTEGERS { multiresult }
+
+FUNCTION {multi.page.check}
+{ 't :=
+  #0 'multiresult :=
+    { multiresult not
+      t empty$ not
+      and
+    }
+    { t #1 #1 substring$
+      duplicate$ "-" =
+      swap$ duplicate$ "," =
+      swap$ "+" =
+      or or
+        { #1 'multiresult := }
+        { t #2 global.max$ substring$ 't := }
+      if$
+    }
+  while$
+  multiresult
+}
+
+% This function doesn't begin a sentence so "pages" isn't capitalized.
+% Other functions that use this should keep that in mind.
+
+FUNCTION {format.pages}
+{ pages empty$
+    { "" }
+    { pages multi.page.check
+        { "pages" pages n.dashify tie.or.space.connect }
+        { "page" pages tie.or.space.connect }
+      if$
+    }
+  if$
+}
+
+% The format.vol.num.pages function is for the volume, number, and page range
+% of a journal article.  We use the format:  vol(number):pages, with some
+% variations for empty fields.  This doesn't begin a sentence.
+
+FUNCTION {format.vol.num.pages}
+{ volume field.or.null
+  number empty$
+    'skip$
+    { "\penalty0 (" number * ")" * *
+      volume empty$
+        { "there's a number but no volume in " cite$ * warning$ }
+        'skip$
+      if$
+    }
+  if$
+  pages empty$
+    'skip$
+    { duplicate$ empty$
+        { pop$ format.pages }
+        { ":\penalty0 " * pages n.dashify * }
+      if$
+    }
+  if$
+}
+
+
+% The format.chapter.pages, if the chapter is present, puts whatever is in the
+% type field (or else "chapter" if type is empty) in front of a chapter number.
+% It then appends the pages, if present.  This doesn't begin a sentence.
+
+FUNCTION {format.chapter.pages}
+{ chapter empty$
+    'format.pages
+    { type empty$
+        { "chapter" }
+        { type "l" change.case$ }
+      if$
+      chapter tie.or.space.connect
+      pages empty$
+        'skip$
+        { ", " * format.pages * }
+      if$
+    }
+  if$
+}
+
+% The format.in.ed.booktitle function is used for starting out a sentence
+% that begins "In <booktitle>", putting an editor before the title if one
+% exists.
+
+FUNCTION {format.in.ed.booktitle}
+{ booktitle empty$
+    { "" }
+    { editor empty$
+        { "In " booktitle emphasize * }
+        { "In " format.editors * ", " * booktitle emphasize * }
+      if$
+    }
+  if$
+}
+
+% The function empty.misc.check complains if all six fields are empty, and
+% if there's been no sorting or alphabetic-label complaint.
+
+FUNCTION {empty.misc.check}
+{ author empty$ title empty$ howpublished empty$
+  month empty$ year empty$ note empty$
+  and and and and and
+#if SORTED
+  key empty$ not and
+#else !SORTED
+#if LAB_ALPH
+  key empty$ not and
+#endif LAB_ALPH
+#endif SORTED
+    { "all relevant fields are empty in " cite$ * warning$ }
+    'skip$
+  if$
+}
+
+% The function format.thesis.type returns either the (case-changed) type field,
+% if it is defined, or else the default string already on the stack
+% (like "Master's thesis" or "PhD thesis").
+
+FUNCTION {format.thesis.type}
+{ type empty$
+    'skip$
+    { pop$
+      type "t" change.case$
+    }
+  if$
+}
+
+% The function format.tr.number makes a string starting with "Technical Report"
+% (or type, if that field is defined), followed by the number if there is one;
+% it returns the starting part (with a case change) even if there is no number.
+% This is used at the beginning of a sentence.
+
+FUNCTION {format.tr.number}
+{ type empty$
+    { "Technical Report" }
+    'type
+  if$
+  number empty$
+    { "t" change.case$ }
+    { number tie.or.space.connect }
+  if$
+}
+
+% Now come the cross-referencing functions (these are invoked because
+% one entry in the database file(s) cross-references another, by giving
+% the other entry's database key in a `crossref' field).  This feature
+% allows one or more titled things that are part of a larger titled
+% thing to cross-reference the larger thing.  These styles allow for
+% five posibilities: (1) an ARTICLE may cross-reference an ARTICLE;
+% (2) a BOOK, (3) INBOOK, or (4) INCOLLECTION may cross-reference a BOOK;
+% or (5) an INPROCEEDINGS may cross-reference a PROCEEDINGS.
+% Each of these is explained in more detail later.
+%
+% An ARTICLE entry type may cross reference another ARTICLE (this is
+% intended for when an entire journal is devoted to a single topic---
+% but since there is no JOURNAL entry type, the journal, too, should be
+% classified as an ARTICLE but without the author and title fields).
+% This will result in two warning messages for the journal's entry
+% if it's included in the reference list, but such is life.
+%
+% format.article.crossref ==
+%  BEGIN
+%       if empty$(key) then
+%           if empty$(journal) then
+%               warning$("need key or journal for " * cite$ *
+%                                               " to crossref " * crossref)
+%               return(" \cite{" * crossref * "}")
+%           else
+%               return("In " * emphasize.correct (journal) *
+%                                               " \cite{" * crossref * "}")
+%               fi
+%       else
+%           return("In " * key * " \cite{" * crossref * "}")
+%       fi
+%  END
+%
+% The other cross-referencing functions are similar, so no "comment version"
+% will be given for them.
+
+FUNCTION {format.article.crossref}
+{ key empty$
+    { journal empty$
+        { "need key or journal for " cite$ * " to crossref " * crossref *
+          warning$
+          ""
+        }
+        { "In {\em " journal * "\/}" * }
+      if$
+    }
+    { "In " key * }
+  if$
+  " \cite{" * crossref * "}" *
+}
+
+% We use just the last names of editors for a cross reference: either
+% "editor", or "editor1 and editor2", or "editor1 et~al." depending on
+% whether there are one, or two, or more than two editors.
+
+FUNCTION {format.crossref.editor}
+{ editor #1 "{vv~}{ll}" format.name$
+  editor num.names$ duplicate$
+  #2 >
+    { pop$ " et~al." * }
+    { #2 <
+        'skip$
+        { editor #2 "{ff }{vv }{ll}{ jj}" format.name$ "others" =
+            { " et~al." * }
+            { " and " * editor #2 "{vv~}{ll}" format.name$ * }
+          if$
+        }
+      if$
+    }
+  if$
+}
+
+% A BOOK (or INBOOK) entry type (assumed to be for a single volume in a
+% multivolume work) may cross reference another BOOK (the entire multivolume).
+% Usually there will be an editor, in which case we use that to construct the
+% cross reference; otherwise we use a nonempty key field or else the series
+% field (since the series gives the title of the multivolume work).
+
+FUNCTION {format.book.crossref}
+{ volume empty$
+    { "empty volume in " cite$ * "'s crossref of " * crossref * warning$
+      "In "
+    }
+    { "Volume" volume tie.or.space.connect
+      " of " *
+    }
+  if$
+  editor empty$
+  editor field.or.null author field.or.null =
+  or
+    { key empty$
+        { series empty$
+            { "need editor, key, or series for " cite$ * " to crossref " *
+              crossref * warning$
+              "" *
+            }
+            { "{\em " * series * "\/}" * }
+          if$
+        }
+        { key * }
+      if$
+    }
+    { format.crossref.editor * }
+  if$
+  " \cite{" * crossref * "}" *
+}
+
+% An INCOLLECTION entry type may cross reference a BOOK (assumed to be the
+% collection), or an INPROCEEDINGS may cross reference a PROCEEDINGS.
+% Often there will be an editor, in which case we use that to construct
+% the cross reference; otherwise we use a nonempty key field or else
+% the booktitle field (which gives the cross-referenced work's title).
+
+FUNCTION {format.incoll.inproc.crossref}
+{ editor empty$
+  editor field.or.null author field.or.null =
+  or
+    { key empty$
+        { booktitle empty$
+            { "need editor, key, or booktitle for " cite$ * " to crossref " *
+              crossref * warning$
+              ""
+            }
+            { "In {\em " booktitle * "\/}" * }
+          if$
+        }
+        { "In " key * }
+      if$
+    }
+    { "In " format.crossref.editor * }
+  if$
+  " \cite{" * crossref * "}" *
+}
+
+% Now we define the type functions for all entry types that may appear
+% in the .BIB file---e.g., functions like `article' and `book'.  These
+% are the routines that actually generate the .BBL-file output for
+% the entry.  These must all precede the READ command.  In addition, the
+% style designer should have a function `default.type' for unknown types.
+% Note: The fields (within each list) are listed in order of appearance,
+% except as described for an `inbook' or a `proceedings'.
+%
+% The article function is for an article in a journal.  An article may
+% CROSSREF another article.
+%       Required fields: author, title, journal, year
+%       Optional fields: volume, number, pages, month, note
+%
+% article ==
+%  BEGIN
+%       output.bibitem
+%       output.check(format.authors,"author")
+%       new.block
+%       output.check(format.title,"title")
+%       new.block
+%       if missing$(crossref) then
+%           output.check(emphasize(journal),"journal")
+%           output(format.vol.num.pages)
+%           output.check(format.date,"year")
+%       else
+%           output.nonnull(format.article.crossref)
+%           output(format.pages)
+%       fi
+%       new.block
+%       output(note)
+%       fin.entry
+%  END
+%
+% The book function is for a whole book.  A book may CROSSREF another book.
+%       Required fields: author or editor, title, publisher, year
+%       Optional fields: volume or number, series, address, edition, month,
+%                       note
+%
+% book ==
+%  BEGIN
+%       if empty$(author) then output.check(format.editors,"author and editor")
+%       else    output.check(format.authors,"author")
+%               if missing$(crossref) then
+%                   either.or.check("author and editor",editor)
+%               fi
+%       fi
+%       new.block
+%       output.check(format.btitle,"title")
+%       if missing$(crossref) then
+%           output(format.bvolume)
+%           new.block
+%           output(format.number.series)
+%           new.sentence
+%           output.check(publisher,"publisher")
+%           output(address)
+%       else
+%           new.block
+%           output.nonnull(format.book.crossref)
+%       fi
+%       output(format.edition)
+%       output.check(format.date,"year")
+%       new.block
+%       output(note)
+%       fin.entry
+%  END
+%
+% The other entry functions are all quite similar, so no "comment version"
+% will be given for them.
+
+FUNCTION {article}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  crossref missing$
+    { journal emphasize "journal" output.check
+      format.vol.num.pages output
+      format.date "year" output.check
+    }
+    { format.article.crossref output.nonnull
+      format.pages output
+    }
+  if$
+  new.block
+  note output
+  fin.entry
+}
+
+FUNCTION {book}
+{ output.bibitem
+  author empty$
+    { format.editors "author and editor" output.check }
+    { format.authors output.nonnull
+      crossref missing$
+        { "author and editor" editor either.or.check }
+        'skip$
+      if$
+    }
+  if$
+  new.block
+  format.btitle "title" output.check
+  crossref missing$
+    { format.bvolume output
+      new.block
+      format.number.series output
+      new.sentence
+      publisher "publisher" output.check
+      address output
+    }
+    { new.block
+      format.book.crossref output.nonnull
+    }
+  if$
+  format.edition output
+  format.date "year" output.check
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% A booklet is a bound thing without a publisher or sponsoring institution.
+%       Required: title
+%       Optional: author, howpublished, address, month, year, note
+
+FUNCTION {booklet}
+{ output.bibitem
+  format.authors output
+  new.block
+  format.title "title" output.check
+  howpublished address new.block.checkb
+  howpublished output
+  address output
+  format.date output
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% For the conference entry type, see inproceedings.
+
+% An inbook is a piece of a book: either a chapter and/or a page range.
+% It may CROSSREF a book.  If there's no volume field, the type field
+% will come before number and series.
+%       Required: author or editor, title, chapter and/or pages, publisher,year
+%       Optional: volume or number, series, type, address, edition, month, note
+
+FUNCTION {inbook}
+{ output.bibitem
+  author empty$
+    { format.editors "author and editor" output.check }
+    { format.authors output.nonnull
+      crossref missing$
+        { "author and editor" editor either.or.check }
+        'skip$
+      if$
+    }
+  if$
+  new.block
+  format.btitle "title" output.check
+  crossref missing$
+    { format.bvolume output
+      format.chapter.pages "chapter and pages" output.check
+      new.block
+      format.number.series output
+      new.sentence
+      publisher "publisher" output.check
+      address output
+    }
+    { format.chapter.pages "chapter and pages" output.check
+      new.block
+      format.book.crossref output.nonnull
+    }
+  if$
+  format.edition output
+  format.date "year" output.check
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% An incollection is like inbook, but where there is a separate title
+% for the referenced thing (and perhaps an editor for the whole).
+% An incollection may CROSSREF a book.
+%       Required: author, title, booktitle, publisher, year
+%       Optional: editor, volume or number, series, type, chapter, pages,
+%                       address, edition, month, note
+
+FUNCTION {incollection}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  crossref missing$
+    { format.in.ed.booktitle "booktitle" output.check
+      format.bvolume output
+      format.number.series output
+      format.chapter.pages output
+      new.sentence
+      publisher "publisher" output.check
+      address output
+      format.edition output
+      format.date "year" output.check
+    }
+    { format.incoll.inproc.crossref output.nonnull
+      format.chapter.pages output
+    }
+  if$
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% An inproceedings is an article in a conference proceedings, and it may
+% CROSSREF a proceedings.  If there's no address field, the month (& year)
+% will appear just before note.
+%       Required: author, title, booktitle, year
+%       Optional: editor, volume or number, series, pages, address, month,
+%                       organization, publisher, note
+
+FUNCTION {inproceedings}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  crossref missing$
+    { format.in.ed.booktitle "booktitle" output.check
+      format.bvolume output
+      format.number.series output
+      format.pages output
+      address empty$
+        { organization publisher new.sentence.checkb
+          organization output
+          publisher output
+          format.date "year" output.check
+        }
+        { address output.nonnull
+          format.date "year" output.check
+          new.sentence
+          organization output
+          publisher output
+        }
+      if$
+    }
+    { format.incoll.inproc.crossref output.nonnull
+      format.pages output
+    }
+  if$
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% The conference function is included for Scribe compatibility.
+
+FUNCTION {conference} { inproceedings }
+
+% A manual is technical documentation.
+%       Required: title
+%       Optional: author, organization, address, edition, month, year, note
+
+FUNCTION {manual}
+{ output.bibitem
+  author empty$
+    { organization empty$
+        'skip$
+        { organization output.nonnull
+          address output
+        }
+      if$
+    }
+    { format.authors output.nonnull }
+  if$
+  new.block
+  format.btitle "title" output.check
+  author empty$
+    { organization empty$
+        { address new.block.checka
+          address output
+        }
+        'skip$
+      if$
+    }
+    { organization address new.block.checkb
+      organization output
+      address output
+    }
+  if$
+  format.edition output
+  format.date output
+  new.block
+  note output
+  fin.entry
+}
+
+% A mastersthesis is a Master's thesis.
+%       Required: author, title, school, year
+%       Optional: type, address, month, note
+
+FUNCTION {mastersthesis}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  "Master's thesis" format.thesis.type output.nonnull
+  school "school" output.check
+  address output
+  format.date "year" output.check
+  new.block
+  note output
+  fin.entry
+}
+
+% A misc is something that doesn't fit elsewhere.
+%       Required: at least one of the `optional' fields
+%       Optional: author, title, howpublished, month, year, note
+
+FUNCTION {misc}
+{ output.bibitem
+  format.authors output
+  title howpublished new.block.checkb
+  format.title output
+  howpublished new.block.checka
+  howpublished output
+  format.date output
+  format.issn output
+  new.block
+  note output
+  fin.entry
+  empty.misc.check
+}
+
+% A phdthesis is like a mastersthesis.
+%       Required: author, title, school, year
+%       Optional: type, address, month, note
+
+FUNCTION {phdthesis}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.btitle "title" output.check
+  new.block
+  "PhD thesis" format.thesis.type output.nonnull
+  school "school" output.check
+  address output
+  format.date "year" output.check
+  new.block
+  note output
+  fin.entry
+}
+
+% A periodical is a publication that appears at regular
+% intervals.  This includes journals, magazines, and newspapers.
+% If there is an organization but no editor field, the
+% organization will appear as the first optional field (we try to
+% make the first block nonempty); if there's no address field,
+% the month (& year) will appear just before note.
+%       Required: title, key
+%       Optional: editor, volume, number, series, address, month, year,
+%                       organization, publisher, note, issn,
+%                       howpublished
+
+FUNCTION {periodical}
+{ output.bibitem
+  editor empty$
+    { organization output }
+    { format.editors output.nonnull }
+  if$
+  new.block
+  title emphasize "title" output.check
+%  format.bvolume output
+%  format.number.series output
+  format.vol.num.pages output
+  format.date output
+  format.issn output
+  new.sentence
+  publisher output
+  address output
+  howpublished new.block.checka
+  howpublished output
+  new.block
+  note output
+  fin.entry
+}
+
+% A proceedings is a conference proceedings.
+% If there is an organization but no editor field, the organization will
+% appear as the first optional field (we try to make the first block nonempty);
+% if there's no address field, the month (& year) will appear just before note.
+%       Required: title, year
+%       Optional: editor, volume or number, series, address, month,
+%                       organization, publisher, note
+
+FUNCTION {proceedings}
+{ output.bibitem
+  editor empty$
+    { organization output }
+    { format.editors output.nonnull }
+  if$
+  new.block
+  format.btitle "title" output.check
+  format.bvolume output
+  format.number.series output
+  address empty$
+    { editor empty$
+        { publisher new.sentence.checka }
+        { organization publisher new.sentence.checkb
+          organization output
+        }
+      if$
+      publisher output
+      format.date "year" output.check
+    }
+    { address output.nonnull
+      format.date "year" output.check
+      new.sentence
+      editor empty$
+        'skip$
+        { organization output }
+      if$
+      publisher output
+    }
+  if$
+  format.isbn output
+  new.block
+  note output
+  fin.entry
+}
+
+% A techreport is a technical report.
+%       Required: author, title, institution, year
+%       Optional: type, number, address, month, note
+
+FUNCTION {techreport}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  format.tr.number output.nonnull
+  institution "institution" output.check
+  address output
+  format.date "year" output.check
+  new.block
+  note output
+  fin.entry
+}
+
+% An unpublished is something that hasn't been published.
+%       Required: author, title, note
+%       Optional: month, year
+
+FUNCTION {unpublished}
+{ output.bibitem
+  format.authors "author" output.check
+  new.block
+  format.title "title" output.check
+  new.block
+  note "note" output.check
+  format.date output
+  fin.entry
+}
+
+% We use entry type `misc' for an unknown type; BibTeX gives a warning.
+
+FUNCTION {default.type} { misc }
+
+% Here are macros for common things that may vary from style to style.
+% Users are encouraged to use these macros.
+%
+% Months are either written out in full or abbreviated
+
+#if MONTH_FULL
+
+MACRO {jan} {"January"}
+
+MACRO {feb} {"February"}
+
+MACRO {mar} {"March"}
+
+MACRO {apr} {"April"}
+
+MACRO {may} {"May"}
+
+MACRO {jun} {"June"}
+
+MACRO {jul} {"July"}
+
+MACRO {aug} {"August"}
+
+MACRO {sep} {"September"}
+
+MACRO {oct} {"October"}
+
+MACRO {nov} {"November"}
+
+MACRO {dec} {"December"}
+
+#else !MONTH_FULL
+
+MACRO {jan} {"Jan."}
+
+MACRO {feb} {"Feb."}
+
+MACRO {mar} {"Mar."}
+
+MACRO {apr} {"Apr."}
+
+MACRO {may} {"May"}
+
+MACRO {jun} {"June"}
+
+MACRO {jul} {"July"}
+
+MACRO {aug} {"Aug."}
+
+MACRO {sep} {"Sept."}
+
+MACRO {oct} {"Oct."}
+
+MACRO {nov} {"Nov."}
+
+MACRO {dec} {"Dec."}
+
+#endif MONTH_FULL
+
+% Journals are either written out in full or abbreviated;
+% the abbreviations are like those found in ACM publications.
+%
+% To get a completely different set of abbreviations, it may be best to make
+% a separate .bib file with nothing but those abbreviations; users could then
+% include that file name as the first argument to the \bibliography command
+
+#if JOUR_FULL
+
+MACRO {acmcs} {"ACM Computing Surveys"}
+
+MACRO {acta} {"Acta Informatica"}
+
+MACRO {cacm} {"Communications of the ACM"}
+
+MACRO {ibmjrd} {"IBM Journal of Research and Development"}
+
+MACRO {ibmsj} {"IBM Systems Journal"}
+
+MACRO {ieeese} {"IEEE Transactions on Software Engineering"}
+
+MACRO {ieeetc} {"IEEE Transactions on Computers"}
+
+MACRO {ieeetcad}
+ {"IEEE Transactions on Computer-Aided Design of Integrated Circuits"}
+
+MACRO {ipl} {"Information Processing Letters"}
+
+MACRO {jacm} {"Journal of the ACM"}
+
+MACRO {jcss} {"Journal of Computer and System Sciences"}
+
+MACRO {scp} {"Science of Computer Programming"}
+
+MACRO {sicomp} {"SIAM Journal on Computing"}
+
+MACRO {tocs} {"ACM Transactions on Computer Systems"}
+
+MACRO {tods} {"ACM Transactions on Database Systems"}
+
+MACRO {tog} {"ACM Transactions on Graphics"}
+
+MACRO {toms} {"ACM Transactions on Mathematical Software"}
+
+MACRO {toois} {"ACM Transactions on Office Information Systems"}
+
+MACRO {toplas} {"ACM Transactions on Programming Languages and Systems"}
+
+MACRO {tcs} {"Theoretical Computer Science"}
+
+#else !JOUR_FULL
+
+MACRO {acmcs} {"ACM Comput. Surv."}
+
+MACRO {acta} {"Acta Inf."}
+
+MACRO {cacm} {"Commun. ACM"}
+
+MACRO {ibmjrd} {"IBM J. Res. Dev."}
+
+MACRO {ibmsj} {"IBM Syst.~J."}
+
+MACRO {ieeese} {"IEEE Trans. Softw. Eng."}
+
+MACRO {ieeetc} {"IEEE Trans. Comput."}
+
+MACRO {ieeetcad}
+ {"IEEE Trans. Comput.-Aided Design Integrated Circuits"}
+
+MACRO {ipl} {"Inf. Process. Lett."}
+
+MACRO {jacm} {"J.~ACM"}
+
+MACRO {jcss} {"J.~Comput. Syst. Sci."}
+
+MACRO {scp} {"Sci. Comput. Programming"}
+
+MACRO {sicomp} {"SIAM J. Comput."}
+
+MACRO {tocs} {"ACM Trans. Comput. Syst."}
+
+MACRO {tods} {"ACM Trans. Database Syst."}
+
+MACRO {tog} {"ACM Trans. Gr."}
+
+MACRO {toms} {"ACM Trans. Math. Softw."}
+
+MACRO {toois} {"ACM Trans. Office Inf. Syst."}
+
+MACRO {toplas} {"ACM Trans. Prog. Lang. Syst."}
+
+MACRO {tcs} {"Theoretical Comput. Sci."}
+
+#endif JOUR_FULL
+
+% Now we read in the .BIB entries.
+
+READ
+
+% The sortify function converts to lower case after purify$ing; it's
+% used in sorting and in computing alphabetic labels after sorting
+%
+% The chop.word(w,len,s) function returns either s or, if the first len
+% letters of s equals w (this comparison is done in the third line of the
+% function's definition), it returns that part of s after w.
+
+#if SORTED
+
+FUNCTION {sortify}
+{ purify$
+  "l" change.case$
+}
+
+INTEGERS { len }
+
+FUNCTION {chop.word}
+{ 's :=
+  'len :=
+  s #1 len substring$ =
+    { s len #1 + global.max$ substring$ }
+    's
+  if$
+}
+
+#else !SORTED
+#if LAB_ALPH
+
+% We need the chop.word stuff for the dubious unsorted-list-with-labels case.
+
+INTEGERS { len }
+
+FUNCTION {chop.word}
+{ 's :=
+  'len :=
+  s #1 len substring$ =
+    { s len #1 + global.max$ substring$ }
+    's
+  if$
+}
+
+#endif LAB_ALPH
+#endif SORTED
+
+% This long comment applies only to alphabetic labels
+%
+% The format.lab.names function makes a short label by using the initials of
+% the von and Last parts of the names (but if there are more than four names,
+% (i.e., people) it truncates after three and adds a superscripted "+";
+% it also adds such a "+" if the last of multiple authors is "others").
+% If there is only one name, and its von and Last parts combined have just
+% a single name-token ("Knuth" has a single token, "Brinch Hansen" has two),
+% we take the first three letters of the last name.  The boolean
+% et.al.char.used tells whether we've used a superscripted "+", so that we
+% know whether to include a LaTeX macro for it.
+%
+% format.lab.names(s) ==
+%  BEGIN
+%       numnames := num.names$(s)
+%       if numnames > 1 then
+%           if numnames > 4 then
+%               namesleft := 3
+%           else
+%               namesleft := numnames
+%           nameptr := 1
+%           nameresult := ""
+%           while namesleft > 0
+%             do
+%               if (name_ptr = numnames) and
+%                    format.name$(s, nameptr, "{ff }{vv }{ll}{ jj}") = "others"
+%                  then nameresult := nameresult * "{\etalchar{+}}"
+%                       et.al.char.used := true
+%                  else nameresult := nameresult *
+%                               format.name$(s, nameptr, "{v{}}{l{}}")
+%               nameptr := nameptr + 1
+%               namesleft := namesleft - 1
+%             od
+%           if numnames > 4 then
+%               nameresult := nameresult * "{\etalchar{+}}"
+%               et.al.char.used := true
+%       else
+%           t := format.name$(s, 1, "{v{}}{l{}}")
+%           if text.length$(t) < 2 then % there's just one name-token
+%               nameresult := text.prefix$(format.name$(s,1,"{ll}"),3)
+%           else
+%               nameresult := t
+%           fi
+%       fi
+%       return nameresult
+%  END
+%
+% Exactly what fields we look at in constructing the primary part of the label
+% depends on the entry type; this selectivity (as opposed to, say, always
+% looking at author, then editor, then key) helps ensure that "ignored" fields,
+% as described in the LaTeX book, really are ignored.  Note that MISC is part
+% of the deepest `else' clause in the nested part of calc.label; thus, any
+% unrecognized entry type in the database is handled correctly.
+%
+% There is one auxiliary function for each of the four different sequences of
+% fields we use.  The first of these functions looks at the author field, and
+% then, if necessary, the key field.  The other three functions, which might
+% look at two fields and the key field, are similar, except that the key field
+% takes precedence over the organization field (for labels---not for sorting).
+%
+% The calc.label function calculates the preliminary label of an entry, which
+% is formed by taking three letters of information from the author or editor or
+% key or organization field (depending on the entry type and on what's empty,
+% but ignoring a leading "The " in the organization), and appending the last
+% two characters (digits) of the year. It is an error if the appropriate fields
+% among author, editor, organization, and key are missing, and we use
+% the first three letters of the cite$ in desperation when this happens.
+% The resulting label has the year part, but not the name part, purify$ed
+% (purify$ing the year allows some sorting shenanigans by the user).
+%
+% This function also calculates the version of the label to be used in sorting.
+%
+% The final label may need a trailing 'a', 'b', etc., to distinguish it from
+% otherwise identical labels, but we can't calculated those "extra.label"s
+% until after sorting.
+%
+% calc.label ==
+%  BEGIN
+%       if type$ = "book" or "inbook" then
+%           author.editor.key.label
+%       else if type$ = "proceedings" then
+%           editor.key.organization.label
+%       else if type$ = "manual" then
+%           author.key.organization.label
+%       else
+%           author.key.label
+%       fi fi fi
+%       label := label * substring$(purify$(field.or.null(year)), -1, 2)
+%               % assuming we will also sort, we calculate a sort.label
+%       sort.label := sortify(label), but use the last four, not two, digits
+%  END
+
+#if LAB_ALPH
+
+INTEGERS { et.al.char.used }
+
+FUNCTION {initialize.et.al.char.used}
+{ #0 'et.al.char.used :=
+}
+
+EXECUTE {initialize.et.al.char.used}
+
+FUNCTION {format.lab.names}
+{ 's :=
+  s num.names$ 'numnames :=
+  numnames #1 >
+    { numnames #4 >
+        { #3 'namesleft := }
+        { numnames 'namesleft := }
+      if$
+      #1 'nameptr :=
+      ""
+        { namesleft #0 > }
+        { nameptr numnames =
+            { s nameptr "{ff }{vv }{ll}{ jj}" format.name$ "others" =
+                { "{\etalchar{+}}" *
+                  #1 'et.al.char.used :=
+                }
+                { s nameptr "{v{}}{l{}}" format.name$ * }
+              if$
+            }
+            { s nameptr "{v{}}{l{}}" format.name$ * }
+          if$
+          nameptr #1 + 'nameptr :=
+          namesleft #1 - 'namesleft :=
+        }
+      while$
+      numnames #4 >
+        { "{\etalchar{+}}" *
+          #1 'et.al.char.used :=
+        }
+        'skip$
+      if$
+    }
+    { s #1 "{v{}}{l{}}" format.name$
+      duplicate$ text.length$ #2 <
+        { pop$ s #1 "{ll}" format.name$ #3 text.prefix$ }
+        'skip$
+      if$
+    }
+  if$
+}
+
+FUNCTION {author.key.label}
+{ author empty$
+    { key empty$
+#if SORTED
+        { cite$ #1 #3 substring$ }
+#else !SORTED           % need warning here because we won't give it later
+        { "for label, need author or key in " cite$ * warning$
+          cite$ #1 #3 substring$
+        }
+#endif SORTED
+        { key #3 text.prefix$ }
+      if$
+    }
+    { author format.lab.names }
+  if$
+}
+
+FUNCTION {author.editor.key.label}
+{ author empty$
+    { editor empty$
+        { key empty$
+#if SORTED
+            { cite$ #1 #3 substring$ }
+#else !SORTED           % need warning here because we won't give it later
+            { "for label, need author, editor, or key in " cite$ * warning$
+              cite$ #1 #3 substring$
+            }
+#endif SORTED
+            { key #3 text.prefix$ }
+          if$
+        }
+        { editor format.lab.names }
+      if$
+    }
+    { author format.lab.names }
+  if$
+}
+
+FUNCTION {author.key.organization.label}
+{ author empty$
+    { key empty$
+        { organization empty$
+#if SORTED
+            { cite$ #1 #3 substring$ }
+#else !SORTED           % need warning here because we won't give it later
+            { "for label, need author, key, or organization in " cite$ *
+                                                                warning$
+              cite$ #1 #3 substring$
+            }
+#endif SORTED
+            { "The " #4 organization chop.word #3 text.prefix$ }
+          if$
+        }
+        { key #3 text.prefix$ }
+      if$
+    }
+    { author format.lab.names }
+  if$
+}
+
+FUNCTION {editor.key.organization.label}
+{ editor empty$
+    { key empty$
+        { organization empty$
+#if SORTED
+            { cite$ #1 #3 substring$ }
+#else !SORTED           % need warning here because we won't give it later
+            { "for label, need editor, key, or organization in " cite$ *
+                                                                warning$
+              cite$ #1 #3 substring$
+            }
+#endif SORTED
+            { "The " #4 organization chop.word #3 text.prefix$ }
+          if$
+        }
+        { key #3 text.prefix$ }
+      if$
+    }
+    { editor format.lab.names }
+  if$
+}
+
+FUNCTION {calc.label}
+{ type$ "book" =
+  type$ "inbook" =
+  or
+    'author.editor.key.label
+    { type$ "proceedings" =
+        'editor.key.organization.label
+        { type$ "manual" =
+            'author.key.organization.label
+            'author.key.label
+          if$
+        }
+      if$
+    }
+  if$
+  duplicate$
+  year field.or.null purify$ #-1 #2 substring$
+  *
+  'label :=
+  year field.or.null purify$ #-1 #4 substring$
+  *
+  sortify 'sort.label :=
+}
+
+% It doesn't seem like a particularly good idea to use an order-of-citation
+% reference list when using alphabetic labels, but we need to have a
+% special pass to calculate labels when this happens.
+
+#if !SORTED
+
+ITERATE {calc.label}
+
+#endif !SORTED
+
+#endif LAB_ALPH
+
+% When sorting, we compute the sortkey by executing "presort" on each entry.
+% The presort key contains a number of "sortify"ed strings, concatenated
+% with multiple blanks between them.  This makes things like "brinch  per"
+% come before "brinch hansen  per".
+%
+% The fields used here are: the sort.label for alphabetic labels (as set by
+% calc.label), followed by the author names (or editor names or organization
+% (with a leading "The " removed) or key field, depending on entry type and on
+% what's empty), followed by year, followed by the first bit of the title
+% (chopping off a leading "The ", "A ", or "An ").
+% Names are formatted: Von Last First Junior.
+% The names within a part will be separated by a single blank
+% (such as "brinch hansen"), two will separate the name parts themselves
+% (except the von and last), three will separate the names,
+% four will separate the names from year (and from label, if alphabetic),
+% and four will separate year from title.
+%
+% The sort.format.names function takes an argument that should be in
+% BibTeX name format, and returns a string containing "   "-separated
+% names in the format described above.  The function is almost the same
+% as format.names.
+
+#if SORTED
+
+FUNCTION {sort.format.names}
+{ 's :=
+  #1 'nameptr :=
+  ""
+  s num.names$ 'numnames :=
+  numnames 'namesleft :=
+    { namesleft #0 > }
+    { nameptr #1 >
+        { "   " * }
+        'skip$
+      if$
+#if NAME_FULL
+      s nameptr "{vv{ } }{ll{ }}{  ff{ }}{  jj{ }}" format.name$ 't :=
+#else
+      s nameptr "{vv{ } }{ll{ }}{  f{ }}{  jj{ }}" format.name$ 't :=
+#endif NAME_FULL
+      nameptr numnames = t "others" = and
+        { "et al" * }
+        { t sortify * }
+      if$
+      nameptr #1 + 'nameptr :=
+      namesleft #1 - 'namesleft :=
+    }
+  while$
+}
+
+% The sort.format.title function returns the argument,
+% but first any leading "A "'s, "An "'s, or "The "'s are removed.
+% The chop.word function uses s, so we need another string variable, t
+
+FUNCTION {sort.format.title}
+{ 't :=
+  "A " #2
+    "An " #3
+      "The " #4 t chop.word
+    chop.word
+  chop.word
+  sortify
+  #1 global.max$ substring$
+}
+
+% The auxiliary functions here, for the presort function, are analogous to
+% the ones for calc.label; the same comments apply, except that the
+% organization field takes precedence here over the key field.  For sorting
+% purposes, we still remove a leading "The " from the organization field.
+
+FUNCTION {author.sort}
+{ author empty$
+    { key empty$
+        { "to sort, need author or key in " cite$ * warning$
+          ""
+        }
+        { key sortify }
+      if$
+    }
+    { author sort.format.names }
+  if$
+}
+
+FUNCTION {author.editor.sort}
+{ author empty$
+    { editor empty$
+        { key empty$
+            { "to sort, need author, editor, or key in " cite$ * warning$
+              ""
+            }
+            { key sortify }
+          if$
+        }
+        { editor sort.format.names }
+      if$
+    }
+    { author sort.format.names }
+  if$
+}
+
+FUNCTION {author.organization.sort}
+{ author empty$
+    { organization empty$
+        { key empty$
+            { "to sort, need author, organization, or key in " cite$ * warning$
+              ""
+            }
+            { key sortify }
+          if$
+        }
+        { "The " #4 organization chop.word sortify }
+      if$
+    }
+    { author sort.format.names }
+  if$
+}
+
+FUNCTION {editor.organization.sort}
+{ editor empty$
+    { organization empty$
+        { key empty$
+            { "to sort, need editor, organization, or key in " cite$ * warning$
+              ""
+            }
+            { key sortify }
+          if$
+        }
+        { "The " #4 organization chop.word sortify }
+      if$
+    }
+    { editor sort.format.names }
+  if$
+}
+
+% There is a limit, entry.max$, on the length of an entry string variable
+% (which is what its sort.key$ is), so we take at most that many characters
+% of the constructed key, and hope there aren't many references that match
+% to that many characters!
+
+FUNCTION {presort}
+#if LAB_ALPH
+{ calc.label
+  sort.label
+  "    "
+  *
+  type$ "book" =
+#else !LAB_ALPH
+{ type$ "book" =
+#endif LAB_ALPH
+  type$ "inbook" =
+  or
+    'author.editor.sort
+    { type$ "proceedings" =
+        'editor.organization.sort
+        { type$ "manual" =
+            'author.organization.sort
+            'author.sort
+          if$
+        }
+      if$
+    }
+  if$
+#if LAB_ALPH
+  *
+#endif LAB_ALPH
+  "    "
+  *
+  year field.or.null sortify
+  *
+  "    "
+  *
+  title field.or.null
+  sort.format.title
+  *
+  #1 entry.max$ substring$
+  'sort.key$ :=
+}
+
+ITERATE {presort}
+
+% And now we can sort
+
+SORT
+
+#endif SORTED
+
+% This long comment applies only to alphabetic labels, when sorted
+%
+% Now comes the final computation for alphabetic labels, putting in the 'a's
+% and 'b's and so forth if required.  This involves two passes: a forward
+% pass to put in the 'b's, 'c's and so on, and a backwards pass
+% to put in the 'a's (we don't want to put in 'a's unless we know there
+% are 'b's).
+% We have to keep track of the longest (in width$ terms) label, for use
+% by the "thebibliography" environment.
+%
+% VAR: longest.label, last.sort.label, next.extra: string
+%      longest.label.width, last.extra.num: integer
+%
+% initialize.longest.label ==
+%  BEGIN
+%       longest.label := ""
+%       last.sort.label := int.to.chr$(0)
+%       next.extra := ""
+%       longest.label.width := 0
+%       last.extra.num := 0
+%  END
+%
+% forward.pass ==
+%  BEGIN
+%       if last.sort.label = sort.label then
+%           last.extra.num := last.extra.num + 1
+%           extra.label := int.to.chr$(last.extra.num)
+%       else
+%           last.extra.num := chr.to.int$("a")
+%           extra.label := ""
+%           last.sort.label := sort.label
+%       fi
+%  END
+%
+% reverse.pass ==
+%  BEGIN
+%       if next.extra = "b" then
+%           extra.label := "a"
+%       fi
+%       label := label * extra.label
+%       if width$(label) > longest.label.width then
+%           longest.label := label
+%           longest.label.width := width$(label)
+%       fi
+%       next.extra := extra.label
+%  END
+
+#if LAB_ALPH
+
+#if SORTED
+
+STRINGS { longest.label last.sort.label next.extra }
+
+INTEGERS { longest.label.width last.extra.num }
+
+FUNCTION {initialize.longest.label}
+{ "" 'longest.label :=
+  #0 int.to.chr$ 'last.sort.label :=
+  "" 'next.extra :=
+  #0 'longest.label.width :=
+  #0 'last.extra.num :=
+}
+
+FUNCTION {forward.pass}
+{ last.sort.label sort.label =
+    { last.extra.num #1 + 'last.extra.num :=
+      last.extra.num int.to.chr$ 'extra.label :=
+    }
+    { "a" chr.to.int$ 'last.extra.num :=
+      "" 'extra.label :=
+      sort.label 'last.sort.label :=
+    }
+  if$
+}
+
+FUNCTION {reverse.pass}
+{ next.extra "b" =
+    { "a" 'extra.label := }
+    'skip$
+  if$
+  label extra.label * 'label :=
+  label width$ longest.label.width >
+    { label 'longest.label :=
+      label width$ 'longest.label.width :=
+    }
+    'skip$
+  if$
+  extra.label 'next.extra :=
+}
+
+EXECUTE {initialize.longest.label}
+
+ITERATE {forward.pass}
+
+REVERSE {reverse.pass}
+
+#else !SORTED
+
+% It still doesn't seem like a good idea to use an order-of-citation
+% reference list when using alphabetic labels, but when this happens we
+% must compute the longest label
+
+STRINGS { longest.label }
+
+INTEGERS { longest.label.width }
+
+FUNCTION {initialize.longest.label}
+{ "" 'longest.label :=
+  #0 'longest.label.width :=
+}
+
+FUNCTION {longest.label.pass}
+{ label width$ longest.label.width >
+    { label 'longest.label :=
+      label width$ 'longest.label.width :=
+    }
+    'skip$
+  if$
+}
+
+EXECUTE {initialize.longest.label}
+
+ITERATE {longest.label.pass}
+
+#endif SORTED
+
+#else !LAB_ALPH
+
+% Now comes the computation for numeric labels.
+% We use either the sorted order or original order.
+% We still have to keep track of the longest (in width$ terms) label, for use
+% by the "thebibliography" environment.
+
+STRINGS { longest.label }
+
+INTEGERS { number.label longest.label.width }
+
+FUNCTION {initialize.longest.label}
+{ "" 'longest.label :=
+  #1 'number.label :=
+  #0 'longest.label.width :=
+}
+
+FUNCTION {longest.label.pass}
+{ number.label int.to.str$ 'label :=
+  number.label #1 + 'number.label :=
+  label width$ longest.label.width >
+    { label 'longest.label :=
+      label width$ 'longest.label.width :=
+    }
+    'skip$
+  if$
+}
+
+EXECUTE {initialize.longest.label}
+
+ITERATE {longest.label.pass}
+
+#endif LAB_ALPH
+
+% Now we're ready to start writing the .BBL file.
+% We begin, if necessary, with a LaTeX macro for unnamed names in an alphabetic
+% label; next comes stuff from the `preamble' command in the database files.
+% Then we give an incantation containing the command
+%     \begin{thebibliography}{...}
+% where the `...' is the longest label.
+%
+% We also call init.state.consts, for use by the output routines.
+
+FUNCTION {begin.bib}
+#if LAB_ALPH
+{ et.al.char.used
+    { "\newcommand{\etalchar}[1]{$^{#1}$}" write$ newline$ }
+    'skip$
+  if$
+  preamble$ empty$
+#else !LAB_ALPH
+{ preamble$ empty$
+#endif LAB_ALPH
+    'skip$
+    { preamble$ write$ newline$ }
+  if$
+  "\begin{thebibliography}{"  longest.label  * "}" * write$ newline$
+}
+
+EXECUTE {begin.bib}
+
+EXECUTE {init.state.consts}
+
+% Now we produce the output for all the entries
+
+ITERATE {call.type$}
+
+% Finally, we finish up by writing the `\end{thebibliography}' command.
+
+FUNCTION {end.bib}
+{ newline$
+  "\end{thebibliography}" write$ newline$
+}
+
+EXECUTE {end.bib}