TY  - JOUR
AU  - D. S. Ushkho
TI  - On the number of singular points of the second group of a cubic system
JO  - Differencialʹnye uravneniâ
PY  - 1993
SP  - 240
EP  - 245
VL  - 29
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1993_29_2_a6/
LA  - ru
ID  - DE_1993_29_2_a6
ER  -