@incollection{JEDP_1978____A18_0,
     author = {Langlais, Michel},
     title = {Sous-solutions d'un probl\`eme unilat\'eral d\'eg\'en\'er\'e},
     booktitle = {},
     series = {Journ\'ees \'equations aux d\'eriv\'ees partielles},
     eid = {18},
     pages = {1--1},
     publisher = {Ecole polytechnique},
     year = {1978},
     language = {fr},
     url = {http://archive.numdam.org/item/JEDP_1978____A18_0/}
}