TY  - JOUR
AU  - Le Khyu Zien
AU  - V. I. Shevchenko
TI  - Homotopy classification of Petrovskii elliptic systems of equations in the plane
JO  - Doklady Akademii Nauk
PY  - 1978
SP  - 26
EP  - 28
VL  - 238
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1978_238_1_a4/
LA  - ru
ID  - DAN_1978_238_1_a4
ER  -