@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},
     year = {1994},
     volume = {48},
     number = {3},
     zbl = {0797.20048},
     url = {http://geodesic.mathdoc.fr/item/SF_1994__48_3_135310/}
}