TY  - JOUR
AU  - A. P. Sadovskii
TI  - Formal orbital normal forms of two-dimensional systems with nonzero linear part
JO  - Differencialʹnye uravneniâ
PY  - 1985
SP  - 1509
EP  - 1516
VL  - 21
IS  - 9
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1985_21_9_a5/
LA  - ru
ID  - DE_1985_21_9_a5
ER  -