@incollection{JEDP_1982____A18_0,
     author = {Pierre L\'evy-Bruhl},
     title = {Conditions suffisantes de r\'esolubilit\'e locale d'op\'erateurs invariants \`a gauche sur des groupes nilpotents},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {18},
     pages = {1--8},
     publisher = {\'Ecole polytechnique},
     year = {1982},
     zbl = {0489.35023},
     language = {fr},
     url = {https://proceedings.centre-mersenne.org/item/JEDP_1982____A18_0/}
}