@article{DM_1991_3_4_a6,
     author = {V. G. Nikonov and D. S. Shevelev},
     title = {Boolean graphs and functions},
     journal = {Diskretnaya Matematika},
     pages = {52--61},
     year = {1991},
     volume = {3},
     number = {4},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DM_1991_3_4_a6/}
}