@article{JSFS_1868__9__204_0,
     author = {JSFS},
     title = {Vari\'et\'es},
     journal = {Journal de la Soci\'et\'e de statistique de Paris},
     pages = {204--220},
     publisher = {Soci\'et\'e de statistique de Paris},
     volume = {9},
     year = {1868},
     language = {fr},
     url = {http://archive.numdam.org/item/JSFS_1868__9__204_0/}
}