Cohomology groups of a groupoid.
Colimits of representable algebra-valued functors.
Compatible tolerances on groupoids
Completely dissociative groupoids
In a groupoid, consider arbitrarily parenthesized expressions on the variables where each appears once and all variables appear in order of their indices. We call these expressions -ary formal products, and denote the set containing all of them by . If are distinct, the statement that and are equal for all values of is a generalized associative law. Among other results, we show that many small groupoids are completely dissociative, meaning that no generalized associative law holds...
Comultiplication on monoids.
Congruence semimodularity of conservative groupoids
Conitnuous increasing weakly bisymmetric groupoids and quasi-groups in .
Construction of all homomorphisms of groupoids
Constructions of (2,n)-varieties of groupoids for n = 7, 8, 9