@article{GDZPPN002255243,
title = {Sur la th\'eorie g\'en\'erale des surfaces unicursales},
journal = {Mathematische Annalen},
volume = {44},
year = {1894},
pages = {428-445},
zbl = {25.1227.02},
url = {http://dml.mathdoc.fr/item/GDZPPN002255243}
}
Humbert, M.G. Sur la théorie générale des surfaces unicursales. Mathematische Annalen, Tome 44 (1894) pp. 428-445. http://gdmltest.u-ga.fr/item/GDZPPN002255243/