TY - JOUR AU - G. G. Kazaryan TI - Estimates of differential operators, and hypoelliptic operators JO - Informatics and Automation PY - 1976 SP - 130 EP - 161 VL - 140 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TRSPY_1976_140_a6/ LA - ru ID - TRSPY_1976_140_a6 ER -