A characterization of ...-classes of semigroups as partial groupoids.
A characterization of some idempotent abelian groupoids
A construction of right groups from a connected groupoid.
A Galois -groupoid for -difference equations
We first recall Malgrange’s definition of -groupoid and we define a Galois -groupoid for -difference equations. Then, we compute explicitly the Galois -groupoid of a constant linear -difference system, and show that it corresponds to the -difference Galois group. Finally, we establish a conjugation between the Galois -groupoids of two equivalent constant linear -difference systems, and define a local Galois -groupoid for Fuchsian linear -difference systems by giving its realizations.
A higher dimensional homotopy sequence.
A homotopy 2-groupoid from a fibration.
A homotopy double groupoid of a Hausdorff space.
A homotopy double groupoid of a Hausdorff space. II: A van Kampen theorem.
A note on associative triples of elements in cancellation groupoids
A note on compatible reflexive relations on quasigroups
A note on entropic groupoids
A note on Lie algebroids which arise from groupoid actions
A note on some identities equivalent to xy=wz
A note on subdirectly irreducible groupoids
A structure theorem for 2-hypergroupoids with topological applications.
Action groupoid in protomodular categories.
An embedding of groupoids and monomorphisms into simple groupoids
An introduction to loopoids
We discuss a concept of loopoid as a non-associative generalization of Brandt groupoid. We introduce and study also an interesting class of more general objects which we call semiloopoids. A differential version of loopoids is intended as a framework for Lagrangian discrete mechanics.
Balanced laws on GD-groupoids.
Balanced laws on ternary GD-groupoids.