TY  - JOUR
AU  - K. B. Sabitov
TI  - Maximum modulus principles for some classes of second-order elliptic and hyperbolic systems
JO  - Differencialʹnye uravneniâ
PY  - 1991
SP  - 272
EP  - 278
VL  - 27
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1991_27_2_a10/
LA  - ru
ID  - DE_1991_27_2_a10
ER  -