@article{DE_1989_25_5_a1,
     author = {S. A. Brykalov},
     title = {Conditions for the existence of solutions that do not require isolation of the linear part in the boundary conditions},
     journal = {Differencialʹnye uravneni\^a},
     pages = {749--757},
     publisher = {mathdoc},
     volume = {25},
     number = {5},
     year = {1989},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1989_25_5_a1/}
}