TY  - JOUR
AU  - L. V. Hörmander
TI  - Hypoelliptic differential equations of second order
JO  - Matematika
PY  - 1968
SP  - 88
EP  - 109
VL  - 12
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MAT_1968_12_2_a3/
LA  - ru
ID  - MAT_1968_12_2_a3
ER  -