@article{DE_1973_9_2_a2,
     author = {V. V. Gudkov and A. Ya. Lepin},
     title = {The solvability of a certain boundary value problem},
     journal = {Differencialʹnye uravneni\^a},
     pages = {220--227},
     publisher = {mathdoc},
     volume = {9},
     number = {2},
     year = {1973},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1973_9_2_a2/}
}