@article{BSMF_1928__56__74_0,
     author = {Grynaeus, E.},
     title = {Sur les syst\`emes de {Pfaff}},
     journal = {Bulletin de la Soci\'et\'e Math\'ematique de France},
     pages = {74--97},
     publisher = {Soci\'et\'e math\'ematique de France},
     volume = {56},
     year = {1928},
     doi = {10.24033/bsmf.1130},
     language = {fr},
     url = {http://www.numdam.org/articles/10.24033/bsmf.1130/}
}