Lemma 20.46.5. Let $(X, \mathcal{O}_ X)$ be a ringed space. The derived category $D(\mathcal{O}_ X)$ is a symmetric monoidal category with tensor product given by derived tensor product with usual associativity and commutativity constraints (for sign rules, see More on Algebra, Section 15.68).

Proof. Omitted. Compare with Lemma 20.46.1. $\square$

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