CHIRIAC, L.; DANILOV, A.; LUPASCO, N.; JO, N.
(Bons Offices, 2018)
A non-empty set G is said to be a groupoid relatively to a binary operation denoted by {•}, if for every ordered pair (a, b) of elements of G there is a unique element ab ∈ G. A groupoid (G, •) is called a quasigroup if ...