%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 7-4-28 on page 498.
%% 
%%  Copyright (C) 2007 Michel Goossens, Frank Mittelbach, Denis Roegel, Sebastian Rahtz, Herbert Vo\ss 
%% 
%%  It may be distributed and/or modified under the conditions
%%  of the LaTeX Project Public License, either version 1.3
%%  of this license or (at your option) any later version.
%% 
%%  See http://www.latex-project.org/lppl.txt for details.
%% 

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{207.83385pt}
\StartShownPreambleCommands
\usepackage[all,poly]{xy}
\StopShownPreambleCommands
\begin{document}
\[\begin{xy} /r1cm/:
  {\xypolygon4"F"{~:{(0,.6)::}}},+(.8,1.3)
 ,{\xypolygon4"B"{~:{(.7,0):(0,.7)::}}}
 ,"F1";"B1"**@{.} ,"F2";"B2"**@{.}
 ,"F3";"B3"**@{.} ,"F4";"B4"**@{.}
\end{xy}
\qquad
\begin{xy} /1cm/:
  {\xypolygon4"F"{~:{(0,.6)::}}},+(.8,1.3)
 ,{\xypolygon4"B"{~:{(.7,0):(0,.7)::}}}
 ,"F1";"B1"**@{.} ,"F2";"B2"**@{.}
 ,"F3";"B3"**@{.} ,"F4";"B4"**@{.}
\end{xy}\]
\end{document}