@article{SJL_1973-1977___1_A4_0,
     author = {Lasry, Jean Michel and Robert, Raoul},
     title = {Acyclicit\'e de l'ensemble des trajectoires d'une \'equation diff\'erentielle multivoque},
     journal = {S\'eminaire sur les \'equations aux d\'eriv\'ees partielles},
     note = {talk:4},
     pages = {1--10},
     year = {1973-1977},
     publisher = {Coll\`ege de France},
     number = {1},
     language = {fr},
     url = {https://www.numdam.org/item/SJL_1973-1977___1_A4_0/}
}