Definition 15.23.9. Let $R$ be a Noetherian domain. Let $M$ be a finite $R$-module. The module $M^{**} = \mathop{\mathrm{Hom}}\nolimits _ R(\mathop{\mathrm{Hom}}\nolimits _ R(M, R), R)$ is called the reflexive hull of $M$.

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