TY  - JOUR
AU  - A. I. Vol'pert
TI  - On the index and normal solvability of boundary value problems for elliptic systems of differential equations in the plane
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 1960
VL  - 15
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_1960_15_3_a15/
LA  - ru
ID  - RM_1960_15_3_a15
ER  -