Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{ARM_1976__12_4_a4, author = {Ha{\l}kowska, Katarzyna}, title = {On some operator defined on equational classes of algebras}, journal = {Archivum mathematicum}, pages = {209--212}, publisher = {mathdoc}, volume = {12}, number = {4}, year = {1976}, mrnumber = {0432510}, zbl = {0352.08003}, language = {en}, url = {http://geodesic.mathdoc.fr/item/ARM_1976__12_4_a4/} }
Hałkowska, Katarzyna. On some operator defined on equational classes of algebras. Archivum mathematicum, Tome 12 (1976) no. 4, pp. 209-212. http://geodesic.mathdoc.fr/item/ARM_1976__12_4_a4/