Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1971_7_11_a23, author = {B. I. Medvedev}, title = {An asymptotic solution of ordinary second order differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {2111--2114}, publisher = {mathdoc}, volume = {7}, number = {11}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_11_a23/} }
B. I. Medvedev. An asymptotic solution of ordinary second order differential equations. Differencialʹnye uravneniâ, Tome 7 (1971) no. 11, pp. 2111-2114. http://geodesic.mathdoc.fr/item/DE_1971_7_11_a23/