Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1988_24_8_a21, author = {E. V. Voskresenskii}, title = {Sharpening of a theorem of {Levinson}}, journal = {Differencialʹnye uravneni\^a}, pages = {1455--1457}, publisher = {mathdoc}, volume = {24}, number = {8}, year = {1988}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1988_24_8_a21/} }
E. V. Voskresenskii. Sharpening of a theorem of Levinson. Differencialʹnye uravneniâ, Tome 24 (1988) no. 8, pp. 1455-1457. http://geodesic.mathdoc.fr/item/DE_1988_24_8_a21/