%% 
%%  The LaTeX Graphics Companion, 2ed (first printing May 2007)
%% 
%%  Example 8-4-20 on page 571.
%% 
%%  Copyright (C) 2007 Michel Goossens, Frank Mittelbach, Denis Roegel, Sebastian Rahtz, Herbert Vo\ss 
%% 
%%  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.
%% 

\documentclass{ttctexa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{111.83385pt}
\AtEndDocument{\end{fmffile}}
\AtBeginDocument{\begin{fmffile}{ftmp}}
\StartShownPreambleCommands
\usepackage{feynmp}
\StopShownPreambleCommands
\begin{document}
\begin{fmfgraph*}(90,70)
 \fmfleft{i1} \fmfright{o1,o2,o3}
 \fmf{fermion,label.side=right,label=$\mathrm{u}$}{i1,v1}
 \fmf{fermion,label.side=right,label=$\mathrm{d}$}{v1,o1}
 \fmf{photon,label.side=left,label.dist=1mm,
      label=$\mathrm{W}^{+}$,tension=0.5}{v1,v2}
 \fmf{fermion,label.side=left,label.dist=1mm,
      label=${\nu}_\mathrm{e}$,tension=0.5}{v2,o2}
 \fmf{fermion,label.side=right,
      label=$\mathrm{e}^{+}$,tension=0.5}{o3,v2}
\end{fmfgraph*}
\end{document}
