TY  - JOUR
AU  - V. N. Vragov
TI  - On the theory of boundary value problems for equations of mixed type in space
JO  - Differencialʹnye uravneniâ
PY  - 1977
SP  - 1098
EP  - 1105
VL  - 13
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1977_13_6_a14/
LA  - ru
ID  - DE_1977_13_6_a14
ER  -