@article{DE_1983_19_1_a8,
     author = {A. I. Ibragimov},
     title = {Solvability of a mixed problem for second-order elliptic equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {56--65},
     publisher = {mathdoc},
     volume = {19},
     number = {1},
     year = {1983},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1983_19_1_a8/}
}