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The following proposition is proved in EGA. Since EGA is somewhat intimidating(and it is written in French), I'm looking for a more readable proof.

EGA IV-3 (8.9.1) (ii) Let $A$ be a ring. Let $X$ be a scheme which is quasi-compact, quasi-separated and locally of finite presentation over $A$. Let $\mathcal{F}$ be an $\mathcal{O}_X$-module of finite presentation. Then there exist a subring $A_0$ of $A$, which is of finite type over $\mathbb{Z}$ and a scheme $X_0$ of finite type over $A_0$ and a coherent $\mathcal{O}_{X_0}$-module $\mathcal{F}_0$ such that $X = X_0\times _{A_0} A$ and $\mathcal{F} = \mathcal{F}_0\otimes_{A_0} A$. Moreover $Supp(\mathcal{F})$ is constructible and closed, and there exists a closed subscheme $Z$ of $X$ such that $|Z| = Supp(\mathcal{F})$ and the canonical morphism $Z \rightarrow X$ is locally of finite presentation.

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