I'm looking for a solution of exercice III.8 (b) in Maclane and Moerdijk's book $\textit{Sheaves in Geometry and Logic}$. Where I can find such a solution ? Or can someone describe the topology J' that makes the equivalence $Sh(\mathcal{C},J)/P \cong Sh(\int_{\mathcal{C}} P,J') $ true ?
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