@article{MOMA_1954__58_176936,
     author = {Walter Wunderlich},
     title = {Eine bemerkenswerte {Fokaleigenschaft} der {D-Kurven} von {Kegeln} 2. {Grades.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {57--62},
     publisher = {mathdoc},
     volume = {58},
     year = {1954},
     zbl = {0055.38704},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1954__58_176936/}
}