TY  - JOUR
AU  - E. V. Voskresenskii
TI  - Sharpening of a theorem of Levinson
JO  - Differencialʹnye uravneniâ
PY  - 1988
SP  - 1455
EP  - 1457
VL  - 24
IS  - 8
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1988_24_8_a21/
LA  - ru
ID  - DE_1988_24_8_a21
ER  -