Kerodon

$\Newextarrow{\xRightarrow}{5,5}{0x21D2}$ $\newcommand\empty{}$
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$

Corollary 11.9.6.5. Let $S$ be a simplicial set. Then the last vertex map $\lambda _{S}^{+}: \operatorname{N}_{\bullet }( \operatorname{{\bf \Delta }}_{S} ) \rightarrow S$ is a weak homotopy equivalence.