@article{106945, author = {Katarzyna Ha\l kowska}, title = {On some operator defined on equational classes of algebras}, journal = {Archivum Mathematicum}, volume = {012}, year = {1976}, pages = {209-212}, zbl = {0352.08003}, mrnumber = {0432510}, language = {en}, url = {http://dml.mathdoc.fr/item/106945} }
Hałkowska, Katarzyna. On some operator defined on equational classes of algebras. Archivum Mathematicum, Tome 012 (1976) pp. 209-212. http://gdmltest.u-ga.fr/item/106945/
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On the subdirect Product of some Equational classes of Algebras, Matematische Nachrichten, 1974, pp. 1-3. (1974)