%% 
%%  Example 03-03-10 
%%  Copyright (C) 2016 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{134.31393pt}

%StartShownPreambleCommands

%StopShownPreambleCommands
\begin{document}
$ {a\overwithdelims() b} \qquad
  {{m\over n}\overwithdelims[]{a+b}} $
\[
 {{m\over n}\overwithdelims\{.{a+b}}
\]
\end{document}
