Abstract. Let R be a commutative domain. We prove that an R-module B is projective if and only if Ext1R(B, T) = 0 for any torsion module T. This answers in the affirmative a question raised by Kaplansky in 1962. © 2007 American Mathematical Society.
|Journal||Transactions of the American Mathematical Society|
|Publication status||Published - 1 May 2008|
- Baer modules
- Mittag-Leffler inverse systems