Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1989_25_2_a1, author = {L. M. Berkovich}, title = {Second-order kindred linear differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {192--201}, publisher = {mathdoc}, volume = {25}, number = {2}, year = {1989}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1989_25_2_a1/} }
L. M. Berkovich. Second-order kindred linear differential equations. Differencialʹnye uravneniâ, Tome 25 (1989) no. 2, pp. 192-201. http://geodesic.mathdoc.fr/item/DE_1989_25_2_a1/