Hereditary Noetherian Prime Rings and Idealizers
Levy, Lawrence S. / Robson, J. Chris
This surveys material previously available only in the research literature. It provides a re-worked and simplified account, with improved clarity, fresh insights and many original results about finite length modules, injective modules and projective modules. It culminates in the authors' surprisingly complete structure theorem for projective modules which involves two independent additive invariants: genus and Steinitz class.