@incollection{SB_1977-1978__20__277_0,
     author = {Malgrange, Bernard},
     title = {L'involutivit\'e des caract\'eristiques des syst\`emes diff\'erentiels et microdiff\'erentiels},
     booktitle = {S\'eminaire Bourbaki : vol. 1977/78, expos\'es 507-524},
     series = {S\'eminaire Bourbaki},
     note = {talk:522},
     pages = {277--289},
     publisher = {Springer-Verlag},
     number = {20},
     year = {1979},
     mrnumber = {554227},
     zbl = {0423.46033},
     language = {fr},
     url = {http://www.numdam.org/item/SB_1977-1978__20__277_0/}
}