@article{DM_1990_2_1_a15,
     author = {N. N. Sharov},
     title = {Upper bounds for the capacity of discrete communication channels},
     journal = {Diskretnaya Matematika},
     pages = {155--157},
     year = {1990},
     volume = {2},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1990_2_1_a15/}
}