TY  - JOUR
AU  - V. A. Ginzburg
TI  - A theorem on the index of differential systems and the geometry of
JO  - Doklady Akademii Nauk
PY  - 1985
SP  - 521
EP  - 525
VL  - 281
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1985_281_3_a0/
LA  - ru
ID  - DAN_1985_281_3_a0
ER  -