Flat covers and flat cotorsion modules

Enochs, Edgar

doi:10.1090/S0002-9939-1984-0754698-X

Flat covers and flat cotorsion modules
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Proc. Amer. Math. Soc. 92 (1984), 179-184 Request permission

Abstract:

It is not known whether modules over an arbitrary ring have flat covers, however for certain modules over commutative noetherian rings they can be shown to exist. These covers, in turn, have an interesting connection with flat cotorsion modules. A complete description of flat cotorsion modules analogous to that given by Harrison for torsion free, cotorsion abelian groups will be given. In this article, $R$ will denote a commutative noetherian ring.

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