Lemma 87.20.7. Let $S$ be a scheme. Let $f : X \to Y$ and $g : Y \to Z$ be a morphism of locally Noetherian formal algebraic spaces over $S$. If $g \circ f$ and $g$ are rig-étale, then so is $f$.

Proof. By Formal Spaces, Remark 86.21.18 this follows from Lemma 87.19.6. $\square$

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