Proposition 3.3.3.3. Let $X$ be a simplicial set. Then there exists another simplicial set $\operatorname{Sd}(X)$ and a morphism $u: X \rightarrow \operatorname{Ex}( \operatorname{Sd}(X) )$ which exhibits $\operatorname{Sd}(X)$ as a subdivision of $X$, in the sense of Notation 3.3.3.2.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$