@article{DAN_1962_147_5_a6,
     author = {T. I. Zelenyak},
     title = {On a problem of {S.} {L.~Sobolev}},
     journal = {Doklady Akademii Nauk},
     pages = {1017--1019},
     year = {1962},
     volume = {147},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1962_147_5_a6/}
}