TY  - JOUR
AU  - V. A. Kondratiev
AU  - S. D. Èidel'man
TI  - On nonnegative solutions of overdetermined systems of partial differential equations
JO  - Doklady Akademii Nauk
PY  - 1977
SP  - 513
EP  - 516
VL  - 237
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1977_237_3_a2/
LA  - ru
ID  - DAN_1977_237_3_a2
ER  -