%% 
%%  Ein Beispiel der DANTE-Edition
%%  Mathematiksatz mit LaTeX
%%  3. Auflage
%%  Beispiel 10-03-4 auf Seite 217.
%%  Copyright (C) 2018 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.
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\documentclass[10pt]{screxa}
\pagestyle{empty}
\setlength\textwidth{352.81416pt}
\AtBeginDocument{\setlength\parindent{0pt}}
%StartShownPreambleCommands

%StopShownPreambleCommands
\begin{document}
\[ \left(
\begin{array}{c@{}c@{}c}
  \begin{array}{|cc|}\hline
    a_{11} & a_{12} \\a_{21} & a_{22} \\\hline
  \end{array} & 0 & 0 \\
  0 & \begin{array}{|ccc|}\hline
        b_{11} & b_{12} & b_{13}\\
        b_{21} & b_{22} & b_{23}\\
        b_{31} & b_{32} & b_{33}\\\hline
      \end{array} & 0 \\
0 & 0 & \begin{array}{|cc|}\hline
          c_{11} & c_{12} \\  c_{21} & c_{22} \\\hline
        \end{array}
\end{array}
\right) \]
\end{document}