TY  - JOUR
AU  - G. M. Buldyk
TI  - The existence of limit cycles of the equation $(1+x)yy'=-P_4(x)-P_2(x)y+\delta y^2$ in a singular case
JO  - Differencialʹnye uravneniâ
PY  - 1978
SP  - 817
EP  - 823
VL  - 14
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1978_14_5_a3/
LA  - ru
ID  - DE_1978_14_5_a3
ER  -