@article{ZNSL_1982_114_a3,
     author = {Z. I. Borevich},
     title = {Periodicity of residues of the number of finite labeled $T_0$-topologies},
     journal = {Zapiski Nauchnykh Seminarov POMI},
     pages = {32--36},
     year = {1982},
     volume = {114},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/ZNSL_1982_114_a3/}
}