On (D-12)-Modules

Abstract

is known that a direct summand of a (D-12)module need not be a (D-12)-module. In this paper we establish some properties of completely (D-12)-modules (modules for which every direct summand is a (D-12)-module). After giving some examples of completely (D-12)-modules, it is proved that every finitely generated weakly supplemented completely (D-12)-module is a finite direct sum of local modules. We also prove that a direct sum of (D-12)-modules need not be a (D-12)-module. Then we deal with some special cases of direct sums of (D-12)-modules. We conclude this work by characterizing some rings in terms of (D-12)-modules.