$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$
11.20
\begin{equation} \begin{gathered}\label{equation:characterize-composition-constraint} \xymatrix@R =50pt@C=50pt{ f^{\ast }( g^{\ast }(Y) ) \ar [r]^-{ \widetilde{f}_{ g^{\ast }(Y) } } \ar [d]^-{ \mu _{f,g}(Y) } & g^{\ast }(Y) \ar [d]^-{ \widetilde{g}_ Y} \\ (g \circ f)^{\ast }(Y) \ar [r]^-{ \widetilde{g \circ f}_{Y} } & Y } \end{gathered} \end{equation}