@incollection{JEDP_1988____A4_0, author = {Enrico Bernardi and Antonio Bove}, title = {Conditions de {Levi} pour le probl\`eme de {Cauchy} pour une classe d'\'equations hyperboliques \`a caract\'eristique triples}, booktitle = {}, series = {Journ\'ees \'equations aux d\'eriv\'ees partielles}, eid = {4}, pages = {1--7}, publisher = {\'Ecole polytechnique}, year = {1988}, zbl = {0676.35053}, mrnumber = {90b:35144b}, language = {fr}, url = {https://proceedings.centre-mersenne.org/item/JEDP_1988____A4_0/} }