@article{DAN_1984_275_3_a4,
     author = {M. V. Zakharyaschev},
     title = {Normal modal logics containing $\mathrm{S}4$},
     journal = {Doklady Akademii Nauk},
     pages = {537--540},
     publisher = {mathdoc},
     volume = {275},
     number = {3},
     year = {1984},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1984_275_3_a4/}
}