TY  - JOUR
AU  - M. V. Dolov
TI  - Limit cycles in the case of the center
JO  - Differencialʹnye uravneniâ
PY  - 1972
SP  - 1691
EP  - 1692
VL  - 8
IS  - 9
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1972_8_9_a18/
LA  - ru
ID  - DE_1972_8_9_a18
ER  -