@book{PPN516784323, title = {Die Geometrie des Raumes Teil 2}, series = {GDML\_Books}, year = {1901}, zbl = {31.0557.03}, language = {ger}, url = {http://dml.mathdoc.fr/item/PPN516784323} }
(éd.). Die Geometrie des Raumes Teil 2. GDML_Books (1901), http://gdmltest.u-ga.fr/item/PPN516784323/