TY  - JOUR
AU  - V. F. Tkachev
TI  - New sufficient conditions for stability, semistability and instability of the limit cycle of the 

JO  - Doklady Akademii Nauk
PY  - 1957
SP  - 564
EP  - 567
VL  - 116
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1957_116_4_a10/
LA  - ru
ID  - DAN_1957_116_4_a10
ER  -