TY  - JOUR
AU  - V. I. Shevchenko
TI  - On the homotopy classification of Douglis--Nirenberg elliptic systems
JO  - Doklady Akademii Nauk
PY  - 1975
SP  - 1275
EP  - 1277
VL  - 225
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1975_225_6_a9/
LA  - ru
ID  - DAN_1975_225_6_a9
ER  -