%% 
%%  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{153.70511pt}
\setlength\parindent{0pt}

\usepackage{pstricks,pst-node}

\begin{document}
\begin{pspicture}(3.5,2)
  \rput[bl](.5,0){\rnode{A}{1}}
  \rput[tr](3.5,2){\rnode{B}{2}}
  \ncarcbox[nodesep=.2cm,boxsize=.4,linearc=.4,%
    arcangle=50,linestyle=dashed]{<->}{A}{B}
  \nbput[nrot=:U]{bottom} \nbput[npos=2]{top}
\end{pspicture}
\end{document}