@article{DE_1989_25_5_a15,
     author = {V. F. Koshchy and A. I. Ropavka},
     title = {Dual methods for solving boundary value problems for systems of elliptic equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {861--867},
     publisher = {mathdoc},
     volume = {25},
     number = {5},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_5_a15/}
}