TY  - JOUR
AU  - I. I. Pleshkan
TI  - A new method of investigation on the isochronism of a system of differential equations
JO  - Doklady Akademii Nauk
PY  - 1968
SP  - 768
EP  - 771
VL  - 182
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1968_182_4_a7/
LA  - ru
ID  - DAN_1968_182_4_a7
ER  -