TY  - JOUR
AU  - E. K. Ershov
TI  - Dependence on a parameter of the rotation number of a differential equation defined on the torus
JO  - Differencialʹnye uravneniâ
PY  - 1975
SP  - 1774
EP  - 1779
VL  - 11
IS  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1975_11_10_a5/
LA  - ru
ID  - DE_1975_11_10_a5
ER  -