%% 
%%  A DANTE-Edition example
%% 
%% 
%%  Copyright (C) 2011 Herbert Voss
%% 
%%  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.
%% 
%% 
%% ==== 
% Show page(s) 1
%% 
\documentclass[]{article}
\pagestyle{empty}
\setlength\textwidth{177.70511pt}
\setlength\parindent{0pt}

\usepackage{pstricks,pst-node}

\begin{document}
\rnode{A}{\psframebox{start}}\qquad%
\rnode{M}{\psframebox{middle}}\qquad
\rnode{B}{\psframebox{end}}
\ncline{->}{A}{M}\ncline{->}{M}{B}
\ncloop[loopsize=0.9,arm=0.4,
  linearc=.2,angleB=180]{->}{A}{B}
\end{document}