TY  - JOUR
AU  - L. A. Cherkas
AU  - L. I. Zhilevich
TI  - The limit cycles of certain differential equations
JO  - Differencialʹnye uravneniâ
PY  - 1972
SP  - 1207
EP  - 1213
VL  - 8
IS  - 7
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1972_8_7_a6/
LA  - ru
ID  - DE_1972_8_7_a6
ER  -