ScalingStacks

Theorem 2.2 (Iitaka). Let $L$ be semiample. Then there exists a surjective morphism $f:X\to Y$ where $Y$ is a normal irreducible variety, $f_{*}\mathcal{O}_{X}=\mathcal{O}_{Y}$, and $L=f^{*}A$ for some ample line bundle $A$ on $Y$. In fact $f=\Phi_{|kL|}$ for all $k$ sufficiently divisible.