Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1984_20_6_a8, author = {A. L. Teptin}, title = {Nonoscillation of solutions and the sign of the {Green} function}, journal = {Differencialʹnye uravneni\^a}, pages = {995--1005}, publisher = {mathdoc}, volume = {20}, number = {6}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1984_20_6_a8/} }
A. L. Teptin. Nonoscillation of solutions and the sign of the Green function. Differencialʹnye uravneniâ, Tome 20 (1984) no. 6, pp. 995-1005. http://geodesic.mathdoc.fr/item/DE_1984_20_6_a8/