@article{AM2_1987__34_137225,
     author = {Georg N\"obeling},
     title = {\"Uber die {Anzahl} der ordnungsgeometrischen {Scheitel} von {Kurven.} {Teil} {I.}},
     journal = {Aequationes mathematicae},
     pages = {82--88},
     year = {1987},
     volume = {34},
     zbl = {0634.51008},
     url = {http://geodesic.mathdoc.fr/item/AM2_1987__34_137225/}
}