@article{DE_1993_29_5_a21,
     author = {D. V. Sivakov},
     title = {On a problem of {A.} {N.~Tikhonov} in a semibounded domain},
     journal = {Differencialʹnye uravneni\^a},
     pages = {905--907},
     year = {1993},
     volume = {29},
     number = {5},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1993_29_5_a21/}
}