%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 6-2-23 on page 345.
%% 
%%  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-node}
\StopShownPreambleCommands
\begin{document}
\hspace*{0.5cm}\rnode{A}{\psframebox{%
   \large\textbf{start}}} to
\rnode{B}{\psframebox{\large\textbf{end}}}
\ncloop[angleA=180,loopsize=0.9,arm=0.5,%
    linearc=.2]{->}{A}{B}
\ncput[npos=1.5,nrot=:U]{%
   \psline{|<->|}(.45,-.2)(-.45,-.2)}
\nbput[npos=1.5,nrot=:D,labelsep=.35cm]%
   {\small\texttt{loopsize}}
\ncloop[angleA=10,angleB=180,%
   linecolor=blue,linearc=.2]{->}{B}{A}
\end{document}