TY  - JOUR
AU  - G. G. Kazaryan
TI  - A~characterization of hypoellipticity by estimates from below
JO  - Informatics and Automation
PY  - 1976
SP  - 162
EP  - 168
VL  - 140
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/TRSPY_1976_140_a7/
LA  - ru
ID  - TRSPY_1976_140_a7
ER  -