@book{PPN593814983,
title = {Principien der Fl\"achentheorie Teil 2},
series = {GDML\_Books},
publisher = {Koch},
year = {1890},
language = {de},
url = {http://dml.mathdoc.fr/item/PPN593814983}
}
Hoppe, Reinhold. Principien der Flächentheorie Teil 2. GDML_Books (1890), http://gdmltest.u-ga.fr/item/PPN593814983/