@book{MSM_1928__32__1_0,
     author = {Riquier, Ch.},
     title = {La m\'ethode des fonctions majorantes et les syst\`emes d'\'equations aux d\'eriv\'ees partielles},
     series = {M\'emorial des sciences math\'ematiques},
     publisher = {Gauthier-Villars},
     number = {32},
     year = {1928},
     language = {fr},
     url = {http://archive.numdam.org/item/MSM_1928__32__1_0/}
}