This paper is a supplement to the author [2]. Let Λ be a ring with identity. If every principal left
ideal in Λ is Λ-projective, then Hattori and Nakano called Λ a left PP-ring in [3],[4]. Nakano …

Introduction. In [3], GM Bergman gave characterizations of semihe-reditary and hereditary
commutative rings in terms of their Pierce stalks. In preparation for these, he also gave …

A ring R is called a left PP-ring if every principal left ideal is projective, equivalently if the left
annihilator l (a) is generated by an idempotent for all a∈ R. These rings seem first to have …

In this paper we study non-commutative pp rings and Baer rings in relation to their quotient
rings. First, we investigate right pp rings and their classical quotient rings. It has been shown …

A ring R is a left qp-ring if each of its left ideals is quasi-projective as a left R-module in the
sense of Wu and Jans. The following results giving the structure of left qp-rings are obtained …

Throughout this paper, all rings are associative rings with identity. The prime radical of a ring
R and the set of nilpotent elements in R are denoted by P (R) and N (R), respectively. In this …

On pp structural matrix rings Page 1 Linear Algebra and its Applications 436 (2012) 3692–3700
Contents lists available at SciVerse ScienceDirect Linear Algebra and its Applications journal …

Throughout the paper, rings are associative rings with identity. A ring is called right duo if
every right ideal is two-sided, and it is called right pp if every principal right ideal is …

In the previous paper [5] the author has studied semi-primary left (resp. right) QF-3 rings,
which is a ring A with the following property: there exists a faithful, projective, injective left …

The purpose of this paper is to study further the ideal and module structure of a commutative
ring with identity, in which every principal ideal is projective. Results concerning particular …