%%
%% This is file `bgteupln.bst',
%% generated with the docstrip utility.
%%
%% The original source files were:
%%
%% bgteucls.dtx  (with options: `bibstyle,long,names1')
%% 
%%   bgteubner class bundle
%% 
%%   Copyright 2003--2015 Harald Harders
%% 
%%   This program 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 opinion) 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 1999/12/01 or later.
%% 
%%   This program consists of all files listed in manifest.txt.
%% 
%%   This BibTeX style is intended to be used with the bgteubner
%%   document class and the babelbib package. It may work together with
%%   other document classes but is unlikely to work without the
%%   babelbib package.
%% 
%%   harald.harders@gmx.de
%% 
ENTRY
  { address
    author
    booktitle
    chapter
    edition
    editor
    howpublished
    institution
    isbn
    issn
    journal
    key
    language
    month
    note
    number
    organization
    pages
    publisher
    school
    series
    title
    type
    url
    volume
    year
  }
  {}
  { label }

INTEGERS
  { output.state
    before.all
    mid.sentence
    after.sentence
    after.block
    before.title
  }
STRINGS
  { s
    t
    language.state
    change.temp
  }
FUNCTION {init.state.consts}
{ #0 'before.all :=
  #1 'mid.sentence :=
  #2 'after.sentence :=
  #3 'after.block :=
  #4 'before.title :=
  "nostate" 'language.state :=
}
FUNCTION {not}
{   { #0 }
    { #1 }
  if$
}
FUNCTION {and}
{   'skip$
    { pop$ #0 }
  if$
}
FUNCTION {or}
{   { pop$ #1 }
    'skip$
  if$
}
FUNCTION {language.change.case}
{
  'change.temp :=
  't :=
  "\btxifchangecase {"
  t change.temp change.case$ *
  "}{" *
  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$
            {
              output.state before.title =
                { "\btxauthorcolon\ " * write$ }
                { add.period$ " " * write$ }
              if$
            }
          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$
  language empty$
    { "empty language in " cite$ * warning$ }
    { language.state language =
        'skip$
        { "\btxselectlanguage {" language * "}" * write$
          newline$
        }
      if$
      language 'language.state :=
    }
  if$
  "\bibitem{" write$
  cite$ write$
  "}" write$
  newline$
  ""
  before.all 'output.state :=
}
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$
}
FUNCTION {after.authors}
{ output.state before.all =
    'skip$
    { before.title 'output.state := }
  if$
}
FUNCTION {new.block.checka}
{ empty$
    'skip$
    'new.block
  if$
}
FUNCTION {new.block.checkb}
{ empty$
  swap$ empty$
  and
    'skip$
    'new.block
  if$
}
FUNCTION {new.block.checkc}
{ empty$
  swap$ empty$
  and
    'skip$
    'after.authors
  if$
}
FUNCTION {new.sentence.checka}
{ empty$
    'skip$
    'new.sentence
  if$
}
FUNCTION {new.sentence.checkb}
{ empty$
  swap$ empty$
  and
    'skip$
    'new.sentence
  if$
}
FUNCTION {field.or.null}
{ duplicate$ empty$
    { pop$ "" }
    'skip$
  if$
}
FUNCTION {namefont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxnamefont {" swap$ * "}" * }
  if$
}
FUNCTION {lastnamefont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxlastnamefont {" swap$ * "}" * }
  if$
}
FUNCTION {titlefont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxtitlefont {" swap$ * "}" * }
  if$
}
FUNCTION {journalfont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxjournalfont {" swap$ * "}" * }
  if$
}
FUNCTION {volumefont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxvolumefont {" swap$ * "}" * }
  if$
}
FUNCTION {etalfont}
{ duplicate$ empty$
    { pop$ "" }
    { "\btxetalfont {" swap$ * "}" * }
  if$
}
INTEGERS { nameptr namesleft numnames }
FUNCTION {format.names}
{ 's :=
  #1 'nameptr :=
  s num.names$ 'numnames :=
  numnames 'namesleft :=
    { namesleft #0 > }
    { nameptr #1 >
      {
        s nameptr "{ff~}{vv~}" format.name$
        s nameptr "{ll}" format.name$ lastnamefont *
        s nameptr "{, jj}" format.name$ * 't :=
          namesleft #1 >
            { ", " * t namefont * }
            { numnames #2 >
                { "\btxandcomma {}" * }
                'skip$
              if$
              s nameptr "{ff~}{vv~}{ll}{, jj}" format.name$ "others" =
                { " " "\btxetalshort {.}" etalfont * * }
                { " \btxandlong {}\ " * t namefont * }
              if$
            }
          if$
        }
        {
          s nameptr "{ll}" format.name$ lastnamefont
          s nameptr "{,~jj}{, ff}{~vv}" format.name$ * namefont
        }
      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 >
        { "\ (\btxeditorslong {})" * }
        { "\ (\btxeditorlong {})" * }
      if$
    }
  if$
}
FUNCTION {format.title}
{ title empty$
    { "" }
    { title "t" language.change.case titlefont }
  if$
}
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$
}
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$
}
FUNCTION {format.btitle}
{ title titlefont
}
FUNCTION {tie.or.space.connect}
{ duplicate$ text.length$ #3 <
    { "~" }
    { "\ " }
  if$
  swap$ * *
}
FUNCTION {volume.tie.or.space.connect}
{ duplicate$ text.length$ #3 <
    { "~" }
    { "\ " }
  if$
  swap$ volumefont * *
}
FUNCTION {either.or.check}
{ empty$
    'pop$
    { "can't use both " swap$ * " fields in " * cite$ * warning$ }
  if$
}
FUNCTION {format.bvolume}
{ volume empty$
    { "" }
    { output.state after.block =
        { "\Btxvolumelong {}" }
        { "\btxvolumelong {}" }
      if$
      volume volume.tie.or.space.connect
      series empty$
        'skip$
        { " \btxofserieslong {}\ " * series titlefont * }
      if$
      "volume and number" number either.or.check
    }
  if$
}
FUNCTION {format.number.series}
{ volume empty$
    { number empty$
        { series field.or.null }
        { output.state mid.sentence =
            { "\btxnumberlong {}" }
            { "\Btxnumberlong {}" }
          if$
          number tie.or.space.connect
          series empty$
            { "there's a number but no series in " cite$ * warning$ }
            { " \btxinserieslong {}\ " * series titlefont * }
          if$
        }
      if$
    }
    { "" }
  if$
}
FUNCTION {format.edition}
{ edition empty$
    { "" }
    {
      output.state mid.sentence =
        { edition "l" language.change.case "~\btxeditionlong {}" * }
        { edition "t" language.change.case "~\btxeditionlong {}" * }
      if$
    }
  if$
}
FUNCTION {format.isbn}
{ isbn empty$
    { "" }
    { "\btxISBN~\btxISBNfont {" isbn * "}" * }
  if$
}
FUNCTION {format.issn}
{ issn empty$
    { "" }
    { "\btxISSN~\btxISSNfont {" issn * "}" * }
  if$
}
FUNCTION {format.url}
{ url empty$
    { "" }
    { "\btxurlfont {" url * "}" * }
  if$
}
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
}
FUNCTION {format.pages}
{ pages empty$
    { "" }
    { pages multi.page.check
        { "\btxpageslong {}" pages n.dashify tie.or.space.connect }
        { "\btxpagelong {}" pages tie.or.space.connect }
      if$
    }
  if$
}

FUNCTION {format.vol.num.pages}
{ volume field.or.null
  number empty$
    'skip$
    { "(" number * ")" * *
      volume empty$
        { "there's a number but no volume in " cite$ * warning$ }
        'skip$
      if$
    }
  if$
  pages empty$
    'skip$
    { duplicate$ empty$
        { pop$ format.pages }
        { ":" * pages n.dashify * }
      if$
    }
  if$
}

FUNCTION {format.chapter.pages}
{ chapter empty$
    'format.pages
    { type empty$
        { "\btxchapterlong {}" }
        { type "l" language.change.case }
      if$
      chapter tie.or.space.connect
      pages empty$
        'skip$
        { ", " * format.pages * }
      if$
    }
  if$
}

FUNCTION {format.in.ed.booktitle}
{ booktitle empty$
    { "" }
    { editor empty$
        { "\Btxinlong {}\ " booktitle titlefont * }
        { "\Btxinlong {}\ " format.editors * ": " * booktitle titlefont * }
      if$
    }
  if$
}

FUNCTION {empty.misc.check}
{ author empty$ title empty$ howpublished empty$
  month empty$ year empty$ note empty$
  and and and and and
  key empty$ not and
    { "all relevant fields are empty in " cite$ * warning$ }
    'skip$
  if$
}

FUNCTION {format.thesis.type}
{ type empty$
    'skip$
    { pop$
      type "t" language.change.case
    }
  if$
}

FUNCTION {format.tr.number}
{
  number empty$
  {
    type empty$
      { "\btxtechreplong {}" }
      { type "t" language.change.case }
    if$
  }
  {
    type empty$
      { "\Btxtechreplong {}" }
      { type "t" language.change.case }
    if$
    number tie.or.space.connect
  }
  if$
}

FUNCTION {format.article.crossref}
{ key empty$
    { journal empty$
        { "need key or journal for " cite$ * " to crossref " * crossref *
          warning$
          ""
        }
        { "\Btxinlong {}\ " journal titlefont * }
      if$
    }
    { "\Btxinlong {}\ " key titlefont * }
  if$
  " \cite{" * crossref * "}" *
}

FUNCTION {format.crossref.editor}
{ editor #1 "{ff~}{vv~}{ll}{, jj}" format.name$ namefont
  editor num.names$ duplicate$
  #2 >
    { pop$ " " "\btxetalshort {.}" etalfont * * }
    { #2 <
        'skip$
        { editor #2 "{ff }{vv~}{ll}{ jj}" format.name$ "others" =
            { " " "\btxetalshort {.}" etalfont * * }
            { " \btxandlong {}\ " * editor #2
              "{ff~}{vv~}{ll}{, jj}" format.name$
              namefont * }
          if$
        }
      if$
    }
  if$
}

FUNCTION {format.book.crossref}
{ volume empty$
    { "empty volume in " cite$ * "'s crossref of " * crossref * warning$
      "\Btxinlong {}\ "
    }
    { "\Btxvolumelong {}" volume volume.tie.or.space.connect
      " \btxofserieslong {}\ " *
    }
  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$
              "" *
            }
            { series titlefont * }
          if$
        }
        { key titlefont * }
      if$
    }
    { format.crossref.editor * }
  if$
  " \cite{" * crossref * "}" *
}

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$
              ""
            }
            { "\Btxinlong {}\ " booktitle titlefont * }
          if$
        }
        { "\Btxinlong {}\ " key titlefont * }
      if$
    }
    { "\Btxinlong {}\ " format.crossref.editor * }
  if$
  " \cite{" * crossref * "}" *
}

FUNCTION {article}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  format.title "title" output.check
  new.block
  crossref missing$
    { journal
      title missing$
        { titlefont }
        { journalfont }
      if$
      "journal" output.check
      format.vol.num.pages output
      format.date "year" output.check
    }
    { format.article.crossref output.nonnull
      format.pages output
    }
  if$
  format.issn output
  new.block
  format.url output
  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$
  after.authors
  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
  format.url output
  note output
  fin.entry
}

FUNCTION {booklet}
{ output.bibitem
  format.authors output
  after.authors
  format.title "title" output.check
  howpublished address new.block.checkb
  howpublished output
  address output
  format.date output
  new.block
  format.url output
  note output
  fin.entry
}

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$
  after.authors
  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
  format.url output
  note output
  fin.entry
}

FUNCTION {incollection}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  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
  format.url output
  note output
  fin.entry
}

FUNCTION {inproceedings}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  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
  format.url output
  note output
  fin.entry
}

FUNCTION {conference} { inproceedings }

FUNCTION {manual}
{ output.bibitem
  author empty$
    { organization empty$
        'skip$
        { organization output.nonnull
          address output
        }
      if$
    }
    { format.authors output.nonnull }
  if$
  after.authors
  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
  format.isbn output
  new.block
  format.url output
  note output
  fin.entry
}

FUNCTION {mastersthesis}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  format.title "title" output.check
  new.block
  "\btxmastthesis {}" format.thesis.type output.nonnull
  school "school" output.check
  address output
  format.date "year" output.check
  new.block
  format.url output
  note output
  fin.entry
}

FUNCTION {misc}
{ output.bibitem
  format.authors output
  title howpublished new.block.checkc
  format.title output
  howpublished new.block.checka
  howpublished output
  format.date output
  format.isbn output
  format.issn output
  new.block
  format.url output
  note output
  fin.entry
  empty.misc.check
}

FUNCTION {phdthesis}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  format.btitle "title" output.check
  new.block
  "\btxphdthesis {}" format.thesis.type output.nonnull
  school "school" output.check
  address output
  format.date "year" output.check
  format.isbn output
  new.block
  format.url output
  note output
  fin.entry
}

FUNCTION {proceedings}
{ output.bibitem
  editor empty$
    { organization output }
    { format.editors output.nonnull }
  if$
  after.authors
  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
  format.url output
  note output
  fin.entry
}

FUNCTION {techreport}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  format.title "title" output.check
  new.block
  format.tr.number output.nonnull
  institution "institution" output.check
  address output
  format.date "year" output.check
  format.isbn output
  new.block
  format.url output
  note output
  fin.entry
}

FUNCTION {unpublished}
{ output.bibitem
  format.authors "author" output.check
  after.authors
  format.title "title" output.check
  new.block
  format.url output
  note "note" output.check
  format.date output
  fin.entry
}

FUNCTION {default.type} { misc }

MACRO {jan} {"\btxmonjanlong {}"}
MACRO {feb} {"\btxmonfeblong {}"}
MACRO {mar} {"\btxmonmarlong {}"}
MACRO {apr} {"\btxmonaprlong {}"}
MACRO {may} {"\btxmonmaylong {}"}
MACRO {jun} {"\btxmonjunlong {}"}
MACRO {jul} {"\btxmonjullong {}"}
MACRO {aug} {"\btxmonauglong {}"}
MACRO {sep} {"\btxmonseplong {}"}
MACRO {oct} {"\btxmonoctlong {}"}
MACRO {nov} {"\btxmonnovlong {}"}
MACRO {dec} {"\btxmondeclong {}"}
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"}

READ

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$
}

FUNCTION {sort.format.names}
{ 's :=
  #1 'nameptr :=
  ""
  s num.names$ 'numnames :=
  numnames 'namesleft :=
    { namesleft #0 > }
    { nameptr #1 >
        { "   " * }
        'skip$
      if$
      s nameptr "{ll{ }}{  ff{ }}{vv{ } }{  jj{ }}" format.name$ 't :=
      nameptr numnames = t "others" = and
        { "et al" * }
        { t sortify * }
      if$
      nameptr #1 + 'nameptr :=
      namesleft #1 - 'namesleft :=
    }
  while$
}

FUNCTION {sort.format.title}
{ 't :=
  "A " #2
    "An " #3
      "The " #4 t chop.word
    chop.word
  chop.word
  sortify
  #1 global.max$ substring$
}

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$
}

FUNCTION {presort}
{ type$ "book" =
  type$ "inbook" =
  or
    'author.editor.sort
    { type$ "proceedings" =
        'editor.organization.sort
        { type$ "manual" =
            'author.organization.sort
            'author.sort
          if$
        }
      if$
    }
  if$
  "    "
  *
  year field.or.null sortify
  *
  "    "
  *
  title field.or.null
  sort.format.title
  *
  #1 entry.max$ substring$
  'sort.key$ :=
}

ITERATE {presort}

SORT

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}

FUNCTION {begin.bib}
{ preamble$ empty$
    'skip$
    { preamble$ write$ newline$ }
  if$
  "\begin{thebibliography}{"  longest.label  * "}" * write$ newline$
  "  \providebibliographyfont{name}{}%" write$ newline$
  "  \providebibliographyfont{lastname}{}%" write$ newline$
  "  \providebibliographyfont{title}{\emph}%" write$ newline$
  "  \providebibliographyfont{etal}{\emph}%" write$ newline$
  "  \providebibliographyfont{journal}{}%" write$ newline$
  "  \providebibliographyfont{volume}{}%" write$ newline$
  "  \providebibliographyfont{ISBN}{\MakeUppercase}%" write$ newline$
  "  \providebibliographyfont{ISSN}{\MakeUppercase}%" write$ newline$
  "  \providebibliographyfont{url}{\url}%" write$ newline$
}

EXECUTE {begin.bib}

EXECUTE {init.state.consts}

ITERATE {call.type$}

FUNCTION {end.bib}
{ newline$
  "\end{thebibliography}" write$ newline$
}

EXECUTE {end.bib}