@article{AL_1991_30_3_a3,
     author = {V. A. Lyubetskii},
     title = {Intuitionistic theory of algebraic systems and},
     journal = {Algebra i logika},
     pages = {320--332},
     publisher = {mathdoc},
     volume = {30},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1991_30_3_a3/}
}