@incollection{JEDP_1987____A8_0,
     author = {Ferruccio Colombini},
     title = {Quelques r\'esultats de non r\'esolubilit\'e locale pour des \'equations hyperboliques},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {8},
     pages = {1--10},
     publisher = {\'Ecole polytechnique},
     year = {1987},
     zbl = {0647.35049},
     mrnumber = {88k:35114},
     language = {fr},
     url = {https://proceedings.centre-mersenne.org/item/JEDP_1987____A8_0/}
}