%% 
%%  Ein Beispiel der DANTE-Edition
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%%  7. Auflage
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%%  Beispiel 15-02-6 auf Seite 256.
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%%  Copyright (C) 2016 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
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\documentclass[]{exaarticle}
\pagestyle{empty}
\setlength\textwidth{121.16928pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands
\usepackage{pst-node}
%StopShownPreambleCommands
\begin{document}
\Cnode[radius=.3cm](.25,0){A}\Cnode[radius=.3cm](2.5,0){B}
\ncarc{->}{A}{B}\ncarc{->}{B}{A}

\vspace{1cm}
\Cnode[radius=.3cm](.25,0){A}\Cnode[radius=.3cm](2.5,0){B}
\ncarc[arcangle=30]{->}{A}{B}
\ncarc[arcangleA=30,arcangleB=-60]{->}{B}{A}
\end{document}