On the quasivarieties generated by finite semigroups.
On the varieties of Cliffordian Semigroups.
On the varieties of completely regular semigroups.
On the word problem for free bands of groups and for free objects in some other varieties of completely regular semigroups.
On two classes of hereditarily finitely based semigroup identities.
On universality of semigroup varieties
A category is called -determined if every set of non-isomorphic -objects such that their endomorphism monoids are isomorphic has a cardinality less than . A quasivariety is called -universal if the lattice of all subquasivarieties of any quasivariety of finite type is a homomorphic image of a sublattice of the lattice of all subquasivarieties of . We say that a variety is var-relatively alg-universal if there exists a proper subvariety of such that homomorphisms of whose image does...
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 clones.
On varieties of combinatorial inverse semigroups I.
On varieties of combinatorial inverse semigroups II.
On varieties of completely regular semigroups.
On varieties of completely regular semigroups II.
On varieties of completely regular semigroups III.
On varieties of regular -semigroups
On varieties of regular -semigroups, II
Operators and products in the lattice of existence varieties of regular semigroups.
Operators , and in the classes of -semigroups and -semirings.
Power monoids and finite J-trivial monoids.
Power pseudovarieties of semigroups I.
Power pseudovarieties of semigroups II.