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@article{ARM_1994__30_1_a1, author = {Havel, V. J. and Klouda, J.}, title = {Closure conditions of commutativity}, journal = {Archivum mathematicum}, pages = {9--16}, publisher = {mathdoc}, volume = {30}, number = {1}, year = {1994}, mrnumber = {1282108}, zbl = {0811.05016}, language = {en}, url = {http://geodesic.mathdoc.fr/item/ARM_1994__30_1_a1/} }
Havel, V. J.; Klouda, J. Closure conditions of commutativity. Archivum mathematicum, Tome 30 (1994) no. 1, pp. 9-16. http://geodesic.mathdoc.fr/item/ARM_1994__30_1_a1/