@article{AL_1981_20_2_a2,
     author = {Yu. N. Mal'tsev},
     title = {On critical algebras},
     journal = {Algebra i logika},
     pages = {155--164},
     year = {1981},
     volume = {20},
     number = {2},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1981_20_2_a2/}
}