TY  - JOUR
AU  - I. I. Pleshkan
TI  - On the isochronicity of systems of two differential equations whose right-hand sides contain common factors
JO  - Differencialʹnye uravneniâ
PY  - 1987
SP  - 981
EP  - 993
VL  - 23
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1987_23_6_a6/
LA  - ru
ID  - DE_1987_23_6_a6
ER  -