@article{AL_1982_21_3_a2,
     author = {M. F. Ra\c{t}\u{a}},
     title = {Nontabularity of the logic ${\rm S}4$ with respect to},
     journal = {Algebra i logika},
     pages = {283--320},
     publisher = {mathdoc},
     volume = {21},
     number = {3},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/AL_1982_21_3_a2/}
}