On a mechanism of defining morphisms in concrete categories
On Categories of Relations
On clones of relations
On distributive homological algebra, I. RE-categories
On distributive homological algebra, II. Theories and models
On distributive homological algebra. III. Homological theories
On epics and dominions of bands.
On simply bireflective subcategories
On the structure of halfdiagonal-halfterminal-symmetric categories with diagonal inversions
The category of all binary relations between arbitrary sets turns out to be a certain symmetric monoidal category Rel with an additional structure characterized by a family of diagonal morphisms, a family of terminal morphisms, and a family of diagonal inversions having certain properties. Using this properties in [11] was given a system of axioms which characterizes the abstract concept of a halfdiagonal-halfterminal-symmetric monoidal category with diagonal inversions (hdht∇s-category)....
One More Categorical Model of Universal Algebra.