Published online by Cambridge University Press: 17 April 2009
Modules whose nonzero endomorphisms are epimorphisms and modules whose nonzero endomorphisms are monomorphisms are considered in this paper. We prove that these two classes of modules are dual to each other via Morita duality. We also prove that a left artinian ring R with Jacobson radical J has a Morita duality if either (1) J/J2 is a central bimodule; or (2) R is artinian right duo and R/J is commutative.