%% 
%%  A DANTE-Edition example
%% 
%%  Example 16-07-3 on page 257.
%% 
%%  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}
\SpecialCoor

\begin{document}
\begin{pspicture}(3,3)
  \cnode(1,3){4pt}{A}
  \rput[B](0,0){\Rnode[vref=20pt]{B}{\Huge A}}
  \rput[B](2,0){\Rnode[vref=20pt]{C}{\Huge a}}
  \psset{angleA=90,nodesepB=4pt}
  \pccurve[angleB=-135]{<-}(B)(A)
  \pccurve[angleB=-45]{<-}(C)(A)
\end{pspicture}
\end{document}