On varieties of non-indexed algebras
On varieties of orgraphs
In this paper we investigate varieties of orgraphs (that is, oriented graphs) as classes of orgraphs closed under isomorphic images, suborgraph identifications and induced suborgraphs, and we study the lattice of varieties of tournament-free orgraphs.
On varieties of pseudo -algebras
In this paper we investigate the relation between the lattice of varieties of pseudo -algebras and the lattice of varieties of lattice ordered groups.
On varieties of regular -semigroups
On varieties of regular -semigroups, II
On von Neumann varieties.
On weak Agassiz systems of algebras
On weak automorphisms of algebras having a basis
On weak automorphisms of quasi-linear algebras
On weakly rigid monounary algebras
On -algebras
One interval in the lattice of partial hyperclones
In this paper the structure of the interval in the lattice of partial hyperclones is determined, where is the clone of all total operations and is the clone of all partial hyperoperations on .
One More Categorical Model of Universal Algebra.
One simple result concerning imprimitivity relations of monoids of transformations and its applications.
One-element extensions in the variety generated by tournaments
We investigate congruences in one-element extensions of algebras in the variety generated by tournaments.
One-element extensions of distributive groupoids
One-generated clones of operations on binary relations
Operads and algebraic geometry.
Operations, homomorphism and update versus relational database systems
Operators and products in the lattice of existence varieties of regular semigroups.