@article{CMH_1959__33_139165,
     author = {K. Voss},
     title = {\"Uber eine spezielle {Klasse} von {Nabelpunkten.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {81--88},
     publisher = {mathdoc},
     volume = {33},
     year = {1959},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/CMH_1959__33_139165/}
}