$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$
9.2
\begin{equation} \begin{gathered}\label{equation:filtered-via-colimits-precise} \xymatrix { \operatorname{\mathcal{E}}_{00} \ar [r] \ar [d] & \operatorname{\mathcal{E}}_{01} \ar [d] \\ \operatorname{\mathcal{E}}_{10} \ar [r] & \operatorname{\mathcal{E}}_{11} } \end{gathered} \end{equation}