@article{SEDP_1978-1979____A12_0,
     author = {M\'etivier, G.},
     title = {Une classe d'op\'erateurs non hypoelliptiques analytiques},
     journal = {S\'eminaire \'Equations aux d\'eriv\'ees partielles (Polytechnique) dit aussi "S\'eminaire Goulaouic-Schwartz"},
     note = {talk:12},
     pages = {1--12},
     publisher = {Ecole Polytechnique, Centre de Math\'ematiques},
     year = {1978-1979},
     mrnumber = {557523},
     zbl = {0419.35022},
     language = {fr},
     url = {http://www.numdam.org/item/SEDP_1978-1979____A12_0/}
}