@article{JSFS_1931__72__296_0,
     author = {Ley},
     title = {Vari\'et\'es},
     journal = {Journal de la soci\'et\'e fran\c{c}aise de statistique},
     pages = {296--299},
     publisher = {Soci\'et\'e de statistique de Paris},
     volume = {72},
     year = {1931},
     language = {fr},
     url = {http://geodesic.mathdoc.fr/item/JSFS_1931__72__296_0/}
}