Geodesic
Direct Sums of Torsion-Free Covers
Canadian journal of mathematics, Tome 25 (1973) no. 5, pp. 1002-1005

Voir la notice de l'article provenant de la source Cambridge University Press

In [4, Theorem 4.1, p. 45], Enochs characterizes the integral domains with the property that the direct product of any family of torsion-free covers is a torsion-free cover. In a setting which includes integral domains as a special case, we consider the corresponding question for direct sums. We use the notion of torsion introduced by Goldie [5]. Among commutative rings, we show that the property “any direct sum of torsion-free covers is a torsion-free cover“ characterizes the semi-simple Artinian rings. 
Cheatham, Thomas. Direct Sums of Torsion-Free Covers. Canadian journal of mathematics, Tome 25 (1973) no. 5, pp. 1002-1005. doi: 10.4153/CJM-1973-107-x
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