@article{JEDP_1982____A3_0, author = {Hounie, Jorge}, title = {On global hypoellipticity of vector fields}, journal = {Journ\'ees \'equations aux d\'eriv\'ees partielles}, eid = {3}, publisher = {Ecole polytechnique}, year = {1982}, zbl = {0489.35032}, mrnumber = {83k:35025}, language = {en}, url = {http://archive.numdam.org/item/JEDP_1982____A3_0/} }