@article{AL_1990_29_6_a3,
     author = {D. V. Lytkina},
     title = {Algebraically nonequivalent constructivization for},
     journal = {Algebra i logika},
     pages = {659--674},
     year = {1990},
     volume = {29},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1990_29_6_a3/}
}