@article{BAG_1985__19_138304,
     author = {Gert B\"ar},
     title = {Konstruktion {Dupinscher} {Indikatrizen} ber\"uhrender {Schraub-} und {Drehfl\"achen}},
     journal = {Beitr\"age zur Algebra und Geometrie},
     pages = {205--216},
     publisher = {mathdoc},
     volume = {19},
     year = {1985},
     zbl = {0565.53007},
     url = {http://geodesic.mathdoc.fr/item/BAG_1985__19_138304/}
}