TY  - JOUR
AU  - Lawrence Corwin
TI  - Necessary and sufficient conditions for hypoelliptic of certain left invariant operators on nilpotent Lie groups II.
JO  - Journal für die reine und angewandte Mathematik
PY  - 1984
SP  - 139
EP  - 152
VL  - 355
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/JRAM_1984__355_152690/
ID  - JRAM_1984__355_152690
ER  -