TY  - JOUR
AU  - M. E. Lerner
TI  - Maximum principles for second order equations of mixed elliptic-hyperbolic type
JO  - Doklady Akademii Nauk
PY  - 1969
SP  - 991
EP  - 994
VL  - 185
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1969_185_5_a5/
LA  - ru
ID  - DAN_1969_185_5_a5
ER  -