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%%  Ein Beispiel der DANTE-Edition
%%  Mathematiksatz mit LaTeX
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%%  Beispiel 10-09-1 auf Seite 228.
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\begin{subequations}
  \begin{align}\label{eq:first1}
    \begin{split}
    \log(q_{f,g,c,y}) &= b_{11}I_{f,g,c,y-1} + b_{12}\log(\mathit{VarP}_{c,y}) + c_{11}\log(P_{c,y}) \\
      & \qquad +c_{12} \log(\mathit{CVarCF}_{f,g,c,y-1}) + \upsilon_c +e_{1,f,g,c,y}
    \end{split} \\[2ex]    \label{eq:first2}
    \begin{split}
    \log(\mathit{CVarCF}_{f,g,c,y}) &= b_{21}I_{f,g,c,y-1}+b_{22}\log(\mathit{VarP}_{c,y})+c_{21}\log(P_{c,y})\\
      & \qquad +c_{22}\log(\mathit{CVarCF}_{f,g,c,y-1}) + \upsilon_c +e_{2,f,g,c,y}
    \end{split}
\end{align}
\end{subequations}
Siehe Gl.~\ref{eq:first1} und Gl.~\ref{eq:first2} \ldots
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