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%%%  @LaTeX3-article{ LaTeX3-VT04-01,
%%%  filename        = "vt04d01.tex",
%%%  archived        = "ctan:/tex-archive/info/ltx3pub/",
%%%  author          = "Pedro J. Aphalo",
%%%  doc-group       = "Volunteer task VT04 about
%%%                     syntax proposal for bibliographical commands",
%%%  title           = "A proposal for citation comands in \LaTeX 3",
%%%  version         = "1.00",
%%%  date            = "2 November 1993",
%%%  time            = "??",
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%%%  author-email    = "Pedro.Aphalo@metla.fi",
%%%  author-address  = "Koivikonkatu 4 B 10 \\
%%%                     SF-77600 Suonenjoki \\
%%%                     Finland",
%%%  abstract        = "This article is a proposal for the
%%%                     syntax of citation commands in
%%%                     \LaTeX 3. The present proposal relies on one
%%%                     set of commands to support
%%%                     all citation schemes, while Rhead's proposal
%%%                     uses three different sets of commands, each
%%%                     supporting only one citation scheme.",
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\documentstyle{l3ms001}
%\documentstyle[a4,cite]{article}
%
% cite.sty is D. Arseneau's style for citations using ranges.
% the looks of the output is slightly changed if this option is removed,
% but the output remains readable.
% cite.sty is available in the CTAN archives in macros\latex\contrib\misc
%
\title{A proposal for citation commands in \LaTeX 3%
       \thanks{This paper is a contribution to task 04, defined in
       `Volunteer work for the \LaTeX 3 project'
       \protect\cite{MittelbachEtAl93}}}
\author{Pedro J. Aphalo\\
        Koivikonkatu 4 B 10\\
        SF-77600 Suonenjoki\\
        Finland\\
        Internet: {\tt Pedro.Aphalo@metla.fi}}
\date{2 November 1993\\
      Version 0.01}

\def\BibTeX{{\rm B\kern-.05em{\sc i\kern-.025em b}\kern-.08em
    T\kern-.1667em\lower.7ex\hbox{E}\kern-.125emX}}

\newcommand{\fakefootnote}[1]{{\noindent\rule{2.5cm}{0.4pt}\\
            \footnotesize #1}}

\begin{document}

\maketitle

\section{Introduction}

There are several recent papers on the problem of what kinds of
citations and bibliographies are commonly used in different disciplines
\cite{Rhe90,Rhe91b,Rhe92b,Rhe92c,Rhe92d,Rhe92e,Rhe92f,Rhe92h,Rhe93,%
Rhend,WonMit91}, and one proposal of how \LaTeX 3 might
support them \cite{Rhe91a,Rhe92a,Rhe92g}.

What follows is my own proposal for the syntax of citation commands in
\LaTeX 3. As such it is an alternative to the proposal of David Rhead.
The main difference between Rhead's scheme and my proposal is that my
proposal does not rely on different citation commands for different
citation schemes.

Although I agree in general with David Rhead's diagnosis of the problem,
I disagree on some basic aspects of the proposed solution.
Rhead \cite{Rhe91a} argues that the three citation schemes:
citation-by-key\footnote{I prefer the more general name:
`citation-by-key' to `reference-by-number' as used by Rhead, because
although the key is usually a number this is not always the case as in
{\tt alpha.bst}.}, author-date and short-form cannot be
accommodated by a single set of commands. However, he accepts that if
possible such a set of commands would be preferable.

As a user, I strongly object to having three different sets of commands
for citations (In disciplines like Biology different schemes are used by
different journals and publishing houses, so having to change from one
scheme to a different one is a real problem). Having different commands
sets also implies that the user has to learn them! I do not object so
much to having different \verb|\bibitem| commands because I use
\BibTeX\ for all my manuscripts, but I think that a consistent syntax
would also be highly desirable.

Preserving the separation of contents and format would provide for a
generic mark-up of manuscripts that could be easily translated to
in-house formats. The normal \LaTeX\ document styles and bibliography
styles could use exactly the same syntax as in-house styles and make
electronic submission for publication much easier than nowadays ---e.g.\
Elsevier Science Publishers has its own generic format for submission of
compuscripts (sic) to {\it any} of their journals \cite{Elsevier93}.

If one considers the possibility of using \LaTeX\ for documents to be
printed but also viewed on-line, using different formats on paper and
screens, the use a single and consistent syntax becomes very important.
So another advantage of abstracting formatting issues into style files is
that the same document can be formatted differently for different
purposes (e.g. \TeX info.).

These are some examples of the advantages of generic mark-up, which
are behind the main objective of this proposal: to achieve a generic
syntax for citations capable of supporting the different citation
schemes.

\section{Rationale}

\sloppy
Citation-by-key is the only scheme currently supported by \LaTeX{}
without extensions.
Consequently the available citation commands are
too limited and citation styles that add new commands have proliferated
(e.g.\ {\tt chicago.sty, harvard.sty, authordate\-.sty}). This is not
good, and \LaTeX 3 should aim at providing a complete set of commands
flexible enough to provide to the needs of different citation schemes
(however, it should provide only a few basic examples of their use in
citation styles and an interface for easily defining new citation styles).

The information needed in different citation schemes is roughly
equivalent, and provided that some discipline is used (e.g.\ use of
\verb|\citeasnoun| and \verb|\citenoname| even for the
citation-by-key scheme) minimal adjustment would be required when
changing a document from one citation style to another. Consequently,
there is no reason from the user's point of view that justifies breaking
one of the design principles of \LaTeX: logic structure and format
should be kept separate. Mittelbach and Rowley \cite[p. 2]{l3d001} state
that `It [\LaTeX] was designed to separate content and form as much as
possible\ldots', and that one of the aims for \LaTeX 3 is to separate
the interfaces used for generic mark-up by the author of a \LaTeX\
document and the specification of how the document elements will be
formatted \cite[p. 5]{l3d001}.

A reason given for having different commands is that some documents use
more than one citation scheme. However, the use of this `mixed' scheme
is not a common situation, and its full support should be addressed by
special styles and not by allowing the simultaneous use of more than one
citation style with \LaTeX's default commands.  Styles supporting the
`mixed' scheme could rely on optional arguments of the same standard
\verb|\cite| commands to switch between citation schemes, and in this
way they could remain compatible with the three simple schemes.

It may even be desirable to have full information available
about the cited work in all citation styles. One reason for this is
that one may need to include the name of authors or dates of publication
in the text independently of the citation scheme being used. Another
reason is that one could use a single \verb|\bibitem| command for all
schemes, and it could also simplify the implementation of mixed citation
schemes.

Keeping the command set consistent and fully implemented in all styles
is the basis for keeping format and structure separate. Such a command
set {\it allows} generic mark-up which makes it possible to change the
citation style without having to edit the whole document to replace
incompatible variations of the \verb|\cite| commands.


\section{Commands}

I propose the following basic set of commands, to be implemented in {\it
all} citation styles. I have tried to reduce the number of commands by
use of optional arguments and \verb|*|, and to keep their syntax
consistent with the rest of \LaTeX. The biggest departure from `normal'
\LaTeX\ syntax is the use of optional arguments {\it within} the curly
brackets of the main argument of \verb|\cite|\footnote{A syntax first
proposed by David Rhead.}. This seems to me the most logical way of
making clear that the optional string arguments remain attached to the
citation specified by each citation key (the order of citations within a
pair of {\it citation brackets} is {\it not} guaranteed to be the same
as the order of the citation keys supplied as argument: styles may
either arrange them in alphabetical or date order, for the author-date
scheme, or in key order for the citation-by-key scheme, or leave them in
the argument's order). The syntax also assumes that styles that format
first citations differently from later ones automatically detect which
ones are first citations (this is possible to achieve, and has been
implemented by Peter Williams in the Harvard family of bibliography
styles). The commands marked $\bullet$ cannot be replaced with simpler
ones, those marked $\circ$ can be replaced with more basic ones (e.g.\
\verb|\cite*| and \verb|\citation|) but are included because they are
used frequently. \verb|\authorof| and \verb|\yearof| are not citation
commands but are very useful as they guarantee consistency of spelling
for author names and consistency for dates (and a spelling checker could
use them to skip author names).

\begin{itemize}

\item
\verb|\cite[|{\it option}\verb|]{[|{\it str}\verb|]|{\it key}%
\verb|[|{\it str}\verb|]}|
where {\it option} is a style specific option, {\it str} is a text
string, and {\it key} is the citation key of a \verb|\bibitem| (or of a
\BibTeX\ database entry), generates a citation string, including
enclosing brackets or footnote(s). Options, if not supported, should be
ignored\footnote{This allows compatibility with other citation styles
that do not need the extra information.}, with a warning except for {\tt
f} and {\tt l} below which should be supported whenever they are
meaningful and quietly ignored otherwise.\\
\verb|\cite[f]{[|{\it str}\verb|]|{\it key}\verb|[|{\it str}\verb|]}| \ldots
treat as first citation of {\it key} even if it is a later instance of
the citation.\\
\verb|\cite[l]{[|{\it str}\verb|]|{\it key}\verb|[|{\it str}\verb|]}| \ldots
treat as later citation of {\it key} even if it is a first instance of
the citation.

\item
\verb|\cite*[|{\it option}\verb|]{[|{\it str}\verb|]|{\it key}%
\verb|[|{\it str}\verb|]}| generates a citation
string, excluding enclosing brackets or footnote. \verb|f| and
\verb|l|, and other options as in \verb|\cite|.
\item[$\circ$]
\verb|\citeaffixed[|{\it option}\verb|]{|{\it str0}%
\verb|}{[|{\it str}\verb|]|{\it key}\verb|[|{\it str}\verb|],...}|
generates a citation string with {\it str0} affixed, including enclosing
brackets or footnote(s). \verb|f| and \verb|l|, and other options as in
\verb|\cite|.
\item[$\circ$]
\verb|\citeasnoun[|{\it option}\verb|]{|{\it key}%
\verb|[|{\it str}\verb|]}| generates a string with author's name(s)
and citation to be used as a noun in a sentence. \verb|f| and \verb|l|,
and other options as in \verb|\cite| above. (Rhead would not include
this command and the next one arguing that the authors' names are not
part of the citation but rather part of the text. I think that he is
only partly right, because at least in the author-date scheme whether
the name list is abbreviated or not depends on whether the names precede
the first or a later instance of a citation. Would
\verb|\authorofandcite| be a better name?)
\item[$\circ$]
\verb|\citepossesive[|{\it option}\verb|]{|{\it key}%
\verb|[|{\it str}\verb|]}| generates a string with author's name(s)
and citation to be used as a possessive in a sentence. \verb|f| and
\verb|l|, and other options as in \verb|\cite| above.
\item
\verb|\citenoname[|{\it option}\verb|]{[|{\it str}\verb|]|{\it key}%
\verb|[|{\it str}\verb|]}|
behaves as \verb|\cite| but does not include the authors in the
author-date scheme. \verb|f| and \verb|l|, and other options as in
\verb|\cite| above. (It is needed for some `MLA' and `MHRA' examples in
Rhead's \cite{Rhe92h} paper. Rhead uses the name \verb|\dcite| for this
command in his proposal for supporting the author-date scheme.)
\item
\verb|\citenoname*[|{\it option}\verb|]{[|{\it str}\verb|]|{\it key}%
\verb|[|{\it str}\verb|]}|
behaves as \verb|\cite*| but does not include the authors in the
author-date scheme. Options as in \verb|\citenoname|.
\item
\verb|\citation{|{\it str}\verb|}| formats a string as a citation ---i.e.
encloses it in brackets or sets it as a footnote.
\item
\verb|\nocite{|{\it key}\verb|,...}| generates no output, but forces
inclusion of references to {\it key} in the list of references.
\item
\verb|\nocite*[|{\it field=regexp}\verb|]| includes in list of
references all entries in bibliography file, or the subset fulfilling
the condition in the optional argument, in which {\it field} is the name
of a field in the \BibTeX\ database file and {regexp} is a regular
expression\footnote{Implementing support for the optional argument
requires changes to the \BibTeX\ program.}.
\item
\verb|\bibref{|{\it key}\verb|}| generates a full reference, not a citation.
(To be used in abstracts in which citations are usually not allowed,
and for writing commented lists of suggested reading.)
\item
\verb|\yearof{|{\it key}\verb|}| year of {\it key}, it is not a citation
---i.e. a reference to {\it key} is not included in list of references.
\item
\verb|\authorof[|{\it option}\verb|]{|{\it key}\verb|}| author or authors
of {\it key}, it is not a citation ---i.e. a reference to {\it key} is
not included in list of references. \verb|f| and \verb|l|, and other
options as in \verb|cite| above.

\end{itemize}

\section{Examples}

A few simple examples of the use of these commands and of how the output
might look for different citation styles [author-date, citation-by-key
(numeric and alphanumeric keys) and short-form schemes] are provided
below. For the short-form scheme fake footnotes are given at the end of
each item in the list of examples, the numbers for numeric keys in the
examples are also faked, but not the authors and titles
\cite{Bor78,Hud18}.

\begin{itemize}
\item[$\triangleright$]
\verb|\cite{Borges78,Hudson18}|\\
(Borges, 1978; Hudson, 1918) or (Hudson, 1918; Borges, 1978)\\
(1,2)\\
{}[Bor78, Hud18] or [Hud18, Bor78]\\
$^{1,2}$\\
\fakefootnote{$^1$ Borges, J. L., {\it El Libro de los Seres
Imaginarios}.\\ $^2$ Hudson, W. H., {\it Far Away and Long Ago.}}

\item[$\triangleright$]
\verb*|\citeaffixed{see }{Borges78,Hudson18}|\\
(see Borges, 1978; Hudson, 1918) or (see Hudson, 1918; Borges, 1978)\\
(see 1,2) or even (1,2)\\
{}[see Bor78, Hud18] or [see Hud18, Bor78]\\
$^{1,2}$\\
\fakefootnote{$^1$ See Borges, J. L., {\it El Libro de los Seres
Imaginarios}.\\ $^2$ See Hudson, W. H., {\it Far Away and Long Ago.}}

\item[$\triangleright$]
\verb|\citeasnoun{Borges78}|\\
Borges (1978)\\
Borges (1)\\
Borges [Bor78]\\
Borges$^1$\\
\fakefootnote{$^1$ Borges, J. L., {\it El Libro de los Seres Imaginarios}.}

\item[$\triangleright$]
\verb|\citepossesive{Borges78}|\\
Borges' (1978)\\
Borges' (1)\\
Borges' [Bor78]\\
Borges'\,$^1$\\
\fakefootnote{$^1$ Borges, J. L., {\it El Libro de los Seres Imaginarios}.}

\item[$\triangleright$]
\verb|\citenoname{Borges78}|\\
(1978)\\
(1)\\
{}[Bor78]\\
$^1$\\
\fakefootnote{$^1$ Borges, J. L., {\it El Libro de los Seres Imaginarios}.}

\item[$\triangleright$]
\verb*|\cite{Borges78[, pp.\ 45--46],Hudson18[, chapter 3]}|\\
(Hudson, 1918, chapter 3; Borges, 1978, pp.\ 45--46) or
(Borges, 1978, pp.\ 45--46; Hudson, 1918, chapter 3)\\
(1, pp.\ 45--46, 2 chapter 3) or
(1 chapter 3, 2 pp.\ 45--46)\\
{}[Bor78 pp.\ 45--46, Hud18 chapter 3] or [Hud18 chapter 3,
Bor78 pp.\ 45--46]\\
$^{1,2}$\\
\fakefootnote{$^1$ Borges, J. L., {\it El Libro de los Seres Imaginarios},
pp.\ 45--46.\\ $^2$ Hudson, W. H., {\it Far Away and Long Ago}, chapter
3.}

\item[$\triangleright$]
\verb*|\citation{see \cite*{Borges78} or \cite*{Hudson18}}|\\
(see Borges, 1978 or Hudson, 1918)\\
(see 1 or 2) or (see 2 or 1), where either 1 or 2 is {\tt Borges78}\\
{}[see Bor78 or Hud18]\\
$^1$\\
\fakefootnote{$^1$ See Borges, J. L., {\it El Libro de los Seres
Imaginarios\/} or Hudson, W. H., {\it Far Away and Long Ago.}}

\end{itemize}

\section{Related problems}

\subsection[]{The problem of pinpointing locations\\ within a reference}

The proposed syntax for \verb|\cite| does not explicitly support style
and language independent pinpointing to pages, sections, chapters, etc.
This could be supported by another layer of commands to be used, if
needed, as {\it str} arguments in \verb|\cite{[|{\it str}\verb|]|{\it
key}\verb|[|{\it str}\verb|],...}|. These commands should not only
provide the pinpoint prefix and typeface, but also scan their argument
to determine whether a plural is needed (e.g.\ `p.' or `pp.' for pages).


Proposed commands are:
\begin{itemize}
\item
 \verb|\pvolume{|{\it volume(s)}\verb|}|
\item
 \verb|\ppart{|{\it parts(s)}\verb|}|
\item
 \verb|\pchapter{|{\it chapter(s)}\verb|}|
\item
 \verb|\psection{|{\it section(s)}\verb|}|
\item
 \verb|\ppage{|{\it page(s)}\verb|}|
\item
 \verb|\pfigure{|{\it figure(s)}\verb|}|
\item
 \verb|\ptable{|{\it table(s)}\verb|}|
\item
 \verb|\pplate{|{\it plates(s)}\verb|}|
\item
 \verb|\pequation{|{\it equations(s)}\verb|}|
\item
 \verb|\ptheorem{|{\it theorem(s)}\verb|}|
\item
 \verb|\ppara{|{\it paragraph(s)}\verb|}|
\item
 \verb|\pline{|{\it line(s)}\verb|}|
\end{itemize}

For example, the command \verb|\cite{Hoff92[\ppage{107--141}]}| would
yield depending on the citation style: [20: 107--141], (Hoff 1992:
107--141),  (Hoff 1992, pp.\ 107--141), or (Hoff 1992, pages 107--141).
The punctuation mark separating the pinpoint from the rest of the
citation is generated automatically by \verb|\ppage|: neither the user,
nor the \verb|\cite| command should provide it.

\sloppy
The above proposal is not a perfect solution
because styles could differ also in the location of the pinpoint: (Hoff
1992, pp.\ 143--179) vs (Pages 143--179 of Hoff 1992). This could be
accommodated by a different syntax of the \verb|\cite| command:
\verb|\cite{Hoff92<p:143--179>}|, being also \verb|\cite{Hoff92<p:257>|
\verb*|[, describes well my feelings]}| valid input. In other words
\verb|<...>| would be used for pinpoints, and \verb|[...]| for strings.
The problem of this approach is that it probably would make the code for
\verb|\cite| complicated. The revised syntax of the \verb|\cite| command
would become:
\begin{itemize}
\item
\verb|\cite[|{\it option}\verb|]{[|{\it str}\verb|]|{\it key}\verb|<|%
{\it pinpoint}\verb|>|\verb|[|{\it str}\verb|],...}|
being arguments enclosed in {\tt []} and {\tt <>} optional, or
\item
\verb|\cite[|{\it option}\verb|]{|{\it key}\verb|<|{\it pinpoint}\verb|>,...}|
if the optional {\it str} arguments are considered redundant.
\end{itemize}
For either of these two last variants of \verb|\cite| the proposed
pinpoint prefixes, listed in the same order as the commands above, are:
{\tt vol:}, {\tt part:}, {\tt ch:}, {\tt sec:}, {\tt p:}, {\tt fig:},
{\tt tab:}, {\tt plate:}, {\tt eq:}, {\tt th:}, {\tt para:}, {\tt
line:}. Compound pinpoints such as
\verb|<vol:3,ch:9,p:1012>| are valid.

\subsection{The problem of signals and other terms}

What Rhead \cite{Rhend} calls ``signals'' are very often used in texts
about law, and less frequently in other disciplines. For these terms,
the typefaces and abbreviations used depend on house styles. An optional
style could define them, but it is arguable whether they differ from the
more general problem of using abbreviations and symbols, except for the
fact that they are widely used. The advantage of providing an optional
style file with their default definitions as part of \LaTeX 3 would be
the standardisation of the names used for this group of commands.
Rhead \cite[chapter 2]{Rhend} proposes a list of such commands as used
in texts about law: \verb|\accord|, \verb|\Accord|,
\verb|\and|, \verb|\butcf|, \verb|\Butcf|, \verb|\butsee|, \verb|\Butsee|,
\verb|\cf|, \verb|\Cf|, \verb|\compare|, \verb|\Compare|, \verb|\contra|,
\verb|\Contra|, \verb|\eg|, \verb|\Eg|, \verb|\etseq|, \verb|\ibid|,
\verb|\Ibid|, \verb|\id|, \verb|\Id|, \verb|\infra|, \verb|\loccit|,
\verb|\opcit|, \verb|\see|, \verb|\See|, \verb|\seealso|, \verb|\Seealso|,
\verb|\seegenerally|, \verb|\Seegenerally|, \verb|\supra|, \verb|\re|,
\verb|\Re|, \verb|\versus|, \verb|\with|. Only some of them are used in
texts unrelated to law, the full list should be implemented only in
law-specific styles. Some of these ``signals'' can be used together with
citations (a) as explanatory text: \verb|\citeaffixed{\see}{Hoff92}|
would print as `(see Hoff 1992)', or (b) as pinpoints:
\verb*|\cite{Hoff92[, \loccit]}| would print as `(Hoff 1992, {\it loc.\
cit.})'. I think that pinpoints like {\it loc.\ cit.} and {\it op.\
cit.} should be handled automatically by citation styles because they
are a formatting issue and have no intrinsic meaning ---e.g.\ (Hoff,
{\it op.\ cit.\/}) in the right context has exactly the same meaning as
(Hoff 1992). In contrast {\it c.f.}, {\it see}, {\it versus}, etc.\
should be specified by the author because they alter the meaning of
citations.

\subsection{The problem of conventions used in texts about law}

The command set proposed cannot support the needs of all legal texts.
References to cases and tables of cases require special commands, but
citations of books, articles in periodicals, etc.\ can most probably be
supported by the commands given above.

Rhead \cite{Rhend} gives an example of how the necessary extensions
could be supported by a law-specific style. A basic example could be
provided as part of \LaTeX 3 so as to provide a guideline for
programmers of styles for legal texts.

\subsection{Undefined citation keys}

The normal behaviour of \verb|\cite| in \LaTeX\ 2.09 is to mark the
missing citation with a `{\tt ?}' in the output file. I find much more
useful for debugging and revising early drafts to have \LaTeX\ output
`{\it citation key}{\tt ?}' in place of the missing citation, and I
think this should be the default behaviour.

\section{Caveat}

While working on this proposal I have deliberately `forgotten' all
problems that have to do with the implementation of the commands. My
philosophy is that first we should have clear what we want, and only
afterwards worry about the implementation. Only as a last resort we
should change the syntax to suit the limitations of \TeX. My idea is
that we should be very open minded about implementation issues, and even
consider {\it heretical} alternatives such as the use of a preprocessor
that reads not only the {\tt .aux} file but also the {\tt .tex} file or
maybe even generates the file to be processed by \TeX\ replacing the
\verb|\cite| commands with something else that is easier for \TeX\ to
process\footnote{As long as the syntax of the commands remains
consistent, support for different schemes could even rely on different
preprocessors!}.

\section{Acknowledgements}

This proposal owes much to the extensive work of David Rhead (mostly
unpublished, but kindly made available by him) and to the authors of the
many citation styles that are available in the CTAN archives. David
Rhead (England), Peter Williams (Australia), John Grace (Scotland), John
Wells (Canada) and Mario Natiello (Sweden) kindly answered my questions
and made useful suggestions. All these contacts took place via e-mail,
so a thank is also due to all those who have made this possible by
creating and maintaining the Internet.

\nocite{Bor78,Hud18,Hoff92}

%\bibliographystyle{unsrt}
%\bibliography{cite}
% the list of references was generated with BibTeX but the .bbl file
% is attached here to keep this document selcontained.

\begin{thebibliography}{10}

\bibitem{MittelbachEtAl93}
F.~Mittelbach, C.~Rowley, and M.~Downes.
\newblock Volunteer work for the {\LaTeX}3 project ({V}ersion 6.2a).
\newblock Public document, {\LaTeX}3 Project, April 1993.
\newblock File {\tt vol-task.tex} archived at Niord.SHSU.edu.

\bibitem{Rhe90}
D.~Rhead.
\newblock Towards {\BibTeX} style-files that implement principal standards.
\newblock {\em \TeX line}, (10):2--8, May 1990.

\bibitem{Rhe91b}
D.~Rhead.
\newblock Some ideas for improving {\LaTeX}.
\newblock University of Nottingham, July 1991.

\bibitem{Rhe92b}
D.~Rhead.
\newblock Short form citations: some examples.
\newblock University of Nottingham, May 1992.

\bibitem{Rhe92c}
D.~Rhead.
\newblock Examples of short form citations when there is a reference list.
\newblock University of Nottingham, September 1992.

\bibitem{Rhe92d}
D.~Rhead.
\newblock Short form citations with cross-references to earlier footnotes for
  full reference.
\newblock University of Nottingham, September 1992.

\bibitem{Rhe92e}
D.~Rhead.
\newblock References numbered according to position in reference-list.
\newblock University of Nottingham, September 1992.

\bibitem{Rhe92f}
D.~Rhead.
\newblock Order of first citation: some examples.
\newblock University of Nottingham, September 1992.

\bibitem{Rhe92h}
D.~Rhead.
\newblock Author-date citations: some examples.
\newblock University of Nottingham, September 1992.

\bibitem{Rhe93}
D.~Rhead.
\newblock The ``operational requirement'' for support of bibliographic
  references by {\LaTeX} 3.
\newblock To appear in {\it TUGboat} {\bf 14}(3), University of Nottingham,
  August 1993.

\bibitem{Rhend}
D.~Rhead.
\newblock Untitled.
\newblock Manuscript about citations in documents about law, not dated.

\bibitem{WonMit91}
R.~Wonneberger and F.~Mittelbach.
\newblock {\BibTeX} reconsidered.
\newblock {\em TUGboat}, 12(1):111--124, 1991.
\newblock {\TeX} 90 Conference Proceedings.

\bibitem{Rhe91a}
D.~Rhead.
\newblock How might {\LaTeX} 3.0 deal with citations and reference lists?
\newblock {\em {\TeX}line}, (13):13--20, September 1991.

\bibitem{Rhe92a}
D.~Rhead.
\newblock Short form citations: how a manual might describe the suggested user
  interface.
\newblock University of Nottingham, May 1992.

\bibitem{Rhe92g}
D.~Rhead.
\newblock Bibliographic references: how a manual might describe the suggested
  user interface.
\newblock University of Nottingham, September 1992.

\bibitem{Elsevier93}
Elsevier~Science Publishers.
\newblock Preparing articles with {\LaTeX}. Instructions to authors for
  preparing compuscripts.
\newblock This is file {\tt instraut.dvi}, included in the ESP-\LaTeX{} package
  archived in the CTAN archives in the directory {\tt
  macros/\-latex/\-contrib/\-elsevier}, 1993.

\bibitem{l3d001}
F.~Mittelbach and C.~Rowley.
\newblock The {\LaTeX}3 project.
\newblock Public, official document, {\LaTeX}3 Project, London, April 1993.
\newblock File {\tt l3d001.tex} archived at Niord.SHSU.edu.

\bibitem{Bor78}
J.~L. Borges.
\newblock {\em El Libro de los Seres Imaginarios}.
\newblock Emec{\'e} Editores, Buenos Aires, 1978.
\newblock This edition first published in 1967 by Kier, Buenos Aires.

\bibitem{Hud18}
W.~H. Hudson.
\newblock {\em Far Away and Long Ago}.
\newblock J. M. Dent and Sons, London, 1918.
\newblock Reprinted 1982, Eland Books, London.

\bibitem{Hoff92}
B.~Hoff.
\newblock {\em The Te of Piglet}.
\newblock Dutton, Penguin Books, New York, 1992.

\end{thebibliography}


\end{document}