@article{120264, author = {Ivan Chajda}, title = {Permutability of congruences in varieties with idempotent operations}, journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica}, volume = {30}, year = {1991}, pages = {33-37}, zbl = {0768.08006}, mrnumber = {1166423}, language = {en}, url = {http://dml.mathdoc.fr/item/120264} }
Chajda, Ivan. Permutability of congruences in varieties with idempotent operations. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 30 (1991) pp. 33-37. http://gdmltest.u-ga.fr/item/120264/
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