TY - JOUR AU - G. G. Kazaryan TI - Estimates of differential operators, and hypoelliptic operators JO - Trudy Matematicheskogo Instituta imeni V.A. Steklova PY - 1976 SP - 130 EP - 161 VL - 140 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/TM_1976_140_a6/ LA - ru ID - TM_1976_140_a6 ER -