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\begin{align}
&\textrm{Min} \sum\limits_{l,m} f_{lm}Y_{lm}\\
&\nonumber \quad \textrm{subject to}\\
&\qquad \sum\limits_{i,j} X_{ijlm}d_{ij}= Y_{lm} , \qquad  \forall l, m\\
&\qquad X_{ijlm}d_{ij}\leq Z_{ij} , \qquad  \forall l, m, i, j
\end{align}

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