@article{DAN_1978_239_6_a0,
     author = {A. V. Bitsadze},
     title = {On a boundary value problem for the {Helmholtz} equation},
     journal = {Doklady Akademii Nauk},
     pages = {1273--1275},
     publisher = {mathdoc},
     volume = {239},
     number = {6},
     year = {1978},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DAN_1978_239_6_a0/}
}