@article{MZM_1982_32_1_a2,
     author = {L. V. Zhizhiashvili},
     title = {Validity of {A.} {N.~Kolmogorov's} theorem for conjugate functions of several variables},
     journal = {Matemati\v{c}eskie zametki},
     pages = {13--21},
     year = {1982},
     volume = {32},
     number = {1},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/MZM_1982_32_1_a2/}
}