%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 6-3-27 on page 378.
%% 
%%  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{135.83385pt}
\StartShownPreambleCommands
\usepackage{pstricks,pst-tree}
\StopShownPreambleCommands
\begin{document}
\psshadowbox[fillcolor=lightgray,
             fillstyle=solid,framearc=0.4]{%
  \psset{tpos=.6}
  \pstree[xbbl=15pt,xbbr=20pt,xbbh=5pt]{\Tc{3pt}}{%
    \TC*^{left}\TC*_{right}}}
\end{document}