@article{DE_1968_4_6_a18,
     author = {P. I. Monastyrnyi},
     title = {The application of the method of orthogonal transformations to boundary value problems with unseparated conditions for systems of differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1140--1146},
     publisher = {mathdoc},
     volume = {4},
     number = {6},
     year = {1968},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1968_4_6_a18/}
}