%%
%% 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{201.70511pt}
\setlength\parindent{0pt}
\usepackage{pstricks,pst-node}
\begin{document}
$\psmatrix[mnode=dia,colsep=1cm]
& [mnode=circle] X \\
Y & Z
\endpsmatrix
\psset{nodesep=3pt,arrows=->}
\ncline{1,2}{2,1}
\ncline{1,2}{2,2}
\ncline[linestyle=dotted]{2,1}{2,2}$
\end{document}
