On a wreath product embedding for regular semigroups.
On complete -ideals in semigroups
On congruence lattices of regular semigroups with Q-inverse transversals.
On ordered regular semigroups with biggest inverses.
On permutability in semigroup varieties
The paper contains characterizations of semigroup varieties whose semigroups with one generator (two generators) are permutable. Here all varieties of regular -semigroups are described in which each semigroup with two generators is permutable.
On quasi-ideals of semirings.
On Regular Right Duo Semigroups.
On sandwich sets and congruences on regular semigroups
Let be a regular semigroup and be the set of its idempotents. We call the sets and one-sided sandwich sets and characterize them abstractly where . For such that , , we call the sandwich set of . We characterize regular semigroups in which all (or all are right zero semigroups (respectively are trivial) in several ways including weak versions of compatibility of the natural order. For every , we also define as the set of all idempotets such that, for any congruence on...
On semilattices of groups whose arrows are epimorphisms.
On some presentations of completely regular semigroups.
On some problems of Petrich concerning Brück and Reilly semigroups.
On structure space of -semigroups
In this paper we introduce the notion of the structure space of -semigroups formed by the class of uniformly strongly prime ideals. We also study separation axioms and compactness property in this structure space.
On the fundamental double four-spiral semigroup.
On the lattice of completely regular monoid varieties.
On the weak regularity of semigroup rings.
On V n -semigroups
In this paper, we give some new characterizations of orthodox semigroups in terms of the set of inverses of idempotents. As a generalization, a new class of regular semigroups, namely Vn-semigroups, is introduced. Also, we give a characterization of Vn-semigroups and investigate some properties of Vn-semigroups. Furthermore, we show that the class of Vn-semigroups is closed under direct products and homomorphic images. However, regular subsemigroups of Vn-semigroups (n ≥ 2) are not necessarily Vn-semigroups...
On varieties of regular -semigroups
On varieties of regular -semigroups, II
Onesided inverses for semigroups.
Operators and products in the lattice of existence varieties of regular semigroups.