@article{JMPA_1887_4_3__305_0,
     author = {Darboux, Gaston},
     title = {Sur la r\'esolution de l'\'equation $dx^2+dy^2+dz^2=ds^2$ et de quelques \'equations analogues},
     journal = {Journal de Math\'ematiques Pures et Appliqu\'ees},
     pages = {305--325},
     publisher = {Gauthier-Villars},
     volume = {4e s{\'e}rie, 3},
     year = {1887},
     language = {fr},
     url = {http://www.numdam.org/item/JMPA_1887_4_3__305_0/}
}