@article{JMPA_1890_4_6__211_0,
     author = {Halphen, G.},
     title = {Sur les formes diff\'erentielles associ\'ees},
     journal = {Journal de Math\'ematiques Pures et Appliqu\'ees},
     pages = {211--230},
     publisher = {Gauthier-Villars},
     volume = {4e s{\'e}rie, 6},
     year = {1890},
     language = {fr},
     url = {http://www.numdam.org/item/JMPA_1890_4_6__211_0/}
}