\begin{thebibliography}{1}

\bibitem{BenKer90}
Jon~L. Bentley and Brian~W. Kernighan.
\newblock Grap---a language for typesetting graphs.
\newblock In {\em Unix Research System Papers}, volume~{II}, pages 109--146.
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\bibitem{Cleve85}
William~S. Cleveland.
\newblock {\em The Elements of Graphing Data}.
\newblock Hobart Press, Summit, New Jersey, 1985, revised 1994.

\bibitem{Cleve93}
William~S. Cleveland.
\newblock {\em Visualizing Data}.
\newblock Hobart Press, Summit, New Jersey, 1993.

\bibitem{Cleve93a}
William~S. Cleveland.
\newblock A model for studying display methods of statistical graphics (with
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\newblock {\em Journal of Computational and Statistical Graphics}, 3, to
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\bibitem{ho:mp3}
John~D. Hobby.
\newblock A user's manual for {MetaPost}.
\newblock Computing Science Technical Report no.~162, AT\&T Bell Laboratories,
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\newblock Available as http://cm.bell-labs.com/cs/cstr/162.ps.gz.

\bibitem{kn:d}
Donald~E. Knuth.
\newblock {\em {\MF} the Program}.
\newblock Addison Wesley, Reading, Massachusetts, 1986.
\newblock Volume D of {\it Computers and Typesetting}.

\bibitem{LaTeXman}
Leslie Lamport.
\newblock {\em {\LaTeX}: A Document Preparation System}.
\newblock Addison Wesley, Reading, Massachusetts, 1986.

\bibitem{Census92}
U.S.~Bureau of~the Census.
\newblock {\em Statistical Abstracts of the United States: 1992}.
\newblock Washington, D.C., 112th edition, 1992.

\bibitem{Tufte83}
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\newblock {\em Visual Display of Quantitative Information}.
\newblock Graphics Press, Box 430, Cheshire, Connecticut 06410, 1983.

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