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Warning Let $A_{\bullet }$ be a semisimplicial abelian group. Then we can still apply Construction to define a subcomplex $\widetilde{ \mathrm{N} }_{\ast }(A)$ of the Moore complex $\mathrm{C}_{\ast }(A)$ (note that the definition of $\widetilde{ \mathrm{N} }_{\ast }(A)$ refers only to the face maps of $A_{\bullet }$). However, it is generally not true that the inclusion map $\widetilde{ \mathrm{N} }_{\ast }(A) \hookrightarrow \mathrm{C}_{\ast }(A)$ induces an isomorphism on homology unless $A_{\bullet }$ can be promoted to a simplicial abelian group.