@article{AL_1982_21_6_a6, author = {D. M. Smirnov}, title = {Universal definability of {Mal'tsev} classes}, journal = {Algebra i logika}, pages = {721--738}, publisher = {mathdoc}, volume = {21}, number = {6}, year = {1982}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/AL_1982_21_6_a6/} }