@article{DE_1969_5_8_a5,
     author = {G. S. Krechetov},
     title = {The connection between the solutions of two systems of differential equations},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1398--1404},
     publisher = {mathdoc},
     volume = {5},
     number = {8},
     year = {1969},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1969_5_8_a5/}
}