@article{SF_1994__48_3_135310, author = {S. Zhang}, title = {Completely regular semigroup varieties generated by {Mal'cev} products with groups.}, journal = {Semigroup forum}, pages = {180--192}, publisher = {mathdoc}, volume = {48}, number = {3}, year = {1994}, zbl = {0797.20048}, url = {http://geodesic.mathdoc.fr/item/SF_1994__48_3_135310/} }