@article{AL_1991_30_3_a4,
     author = {A. G. Pinus},
     title = {L\"owenheim numbers for skeletons of varieties of {Boolean}},
     journal = {Algebra i logika},
     pages = {333--354},
     publisher = {mathdoc},
     volume = {30},
     number = {3},
     year = {1991},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1991_30_3_a4/}
}