Flatness and amalgamation in semigroups.
Flatness and projectivity in commutative regular semigroups.
Flatness in varieties of normal bands.
Flatness Properties of Monocyclic Acts.
Formal language theory and the geometry of 3-manifolds.
Fortsetzung stetiger Homomorphismen von ...-Halbgruppen.
Four-part semigroups - semigroups of Boolean operations
Four-part semigroups form a new class of semigroups which became important when sets of Boolean operations which are closed under the binary superposition operation f + g := f(g,...,g), were studied. In this paper we describe the lattice of all subsemigroups of an arbitrary four-part semigroup, determine regular and idempotent elements, regular and idempotent subsemigroups, homomorphic images, Green's relations, and prove a representation theorem for four-part semigroups.
Free burnside semigroups
This paper surveys the area of Free Burnside Semigroups. The theory of these semigroups, as is the case for groups, is far from being completely known. For semigroups, the most impressive results were obtained in the last 10 years. In this paper we give priority to the mathematical treatment of the problem and do not stress too much neither motivation nor the historical aspects. No proofs are presented in this paper, but we tried to give as many examples as was possible.
Free Burnside Semigroups
This paper surveys the area of Free Burnside Semigroups. The theory of these semigroups, as is the case for groups, is far from being completely known. For semigroups, the most impressive results were obtained in the last 10 years. In this paper we give priority to the mathematical treatment of the problem and do not stress too much neither motivation nor the historical aspects. No proofs are presented in this paper, but we tried to give as many examples as was possible.
Free inverse semigroups.
Free inverse semigroups.
Free inverse semigroups
Free inverse semigroups
Free left distributive semigroups
Free locally inverse *-semigroups
Free products of normal bands.
Free products with amalgamation of semigroups.
Free semigroups and unitary group representations
Free topological inverse semigroups.
F-regular and F-orthodox semigroups.