TY  - JOUR
AU  - N. P. Morozov
TI  - Periodic solutions of the equation $\ddot x+\lambda f(x,\dot x)\dot x+x=0$
JO  - Differencialʹnye uravneniâ
PY  - 1988
SP  - 1826
EP  - 1828
VL  - 24
IS  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1988_24_10_a24/
LA  - ru
ID  - DE_1988_24_10_a24
ER  -