%% 
%%  A DANTE-Edition example
%% 
%%  Example 16-02-17 on page 234.
%% 
%%  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}(3.5,3)
  \rput[tl](0,3){\rnode{A}{\psframebox{Kn. A}}}
  \rput[br](3.5,0){\ovalnode{B}{Kn. B}}
  \ncangles[angleA=-90,arm=.4cm,linearc=.15]{->}{A}{B}
  \ncput*{d}
  \nbput[nrot=:D,npos=2.5]{par}
\end{pspicture}
\end{document}