@article{DAN_1980_254_5_a5,
     author = {A. S. Dzhafarov},
     title = {Some classes of differentiable functions},
     journal = {Doklady Akademii Nauk},
     pages = {1047--1051},
     year = {1980},
     volume = {254},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1980_254_5_a5/}
}