@article{SJL_1972____A7_0,
     author = {Chazarain, Jacques and Piriou, Alain},
     title = {Remarques sur la caract\'erisation des probl\`emes mixtes bien pos\'es pour un op\'erateur hyperbolique},
     journal = {S\'eminaire sur les \'equations aux d\'eriv\'ees partielles},
     note = {talk:4},
     pages = {1--14},
     year = {1972},
     publisher = {Coll\`ege de France},
     language = {fr},
     url = {https://www.numdam.org/item/SJL_1972____A7_0/}
}