Corollary 9.4.6.8. Let $V: \operatorname{\mathcal{E}}\rightarrow \operatorname{\mathcal{D}}$ and $U: \operatorname{\mathcal{D}}\rightarrow \operatorname{\mathcal{C}}$ be flat inner fibrations of simplicial sets. Then the composite map $(U \circ V): \operatorname{\mathcal{E}}\rightarrow \operatorname{\mathcal{C}}$ is also a flat inner fibration.
$\Newextarrow{\xhookrightarrow}{10,10}{0x21AA}$