@article{GDZPPN002249286,
title = {Ueber neue Focaleigenschaften der Fl\"achen 2. Grades},
journal = {Mathematische Annalen},
volume = {27},
year = {1886},
pages = {253-271},
zbl = {18.0755.02},
url = {http://dml.mathdoc.fr/item/GDZPPN002249286}
}
Staude. Ueber neue Focaleigenschaften der Flächen 2. Grades. Mathematische Annalen, Tome 27 (1886) pp. 253-271. http://gdmltest.u-ga.fr/item/GDZPPN002249286/