@article{DE_1967_3_7_a3,
     author = {A. V. Kostin},
     title = {Asymptotic series in the theory of nonlinear systems of ordinary differential equations. {II}},
     journal = {Differencialʹnye uravneni\^a},
     pages = {1070--1077},
     publisher = {mathdoc},
     volume = {3},
     number = {7},
     year = {1967},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1967_3_7_a3/}
}