TY  - JOUR
AU  - K. B. Sabitov
TI  - The maximum principle for systems of second-order equations of mixed type
JO  - Differencialʹnye uravneniâ
PY  - 1990
SP  - 488
EP  - 494
VL  - 26
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1990_26_3_a16/
LA  - ru
ID  - DE_1990_26_3_a16
ER  -