On a class of n-ary quasigroups. Alimpic, Branka P. — 1981 Publications de l'Institut Mathématique. Nouvelle Série
Completely Regular and Orthodox Congruences on Regular Semigroups Branka Alimpić; Dragica N. Krgović — 1993 Publications de l'Institut Mathématique
Completely regular and orthodox congruences on regular semigroups. Alimpić, Branka P.; Krgović, Dragica N. — 1993 Publications de l'Institut Mathématique. Nouvelle Série