@article{MZ_1923__16_174957, author = {P. Funk}, title = {\"Uber {Fl\"achen} mit einem festen {Abstand} der konjugierten {Punkte} .}, journal = {Mathematische Zeitschrift}, pages = {159--162}, publisher = {mathdoc}, volume = {16}, year = {1923}, zbl = {49.0510.01}, url = {http://geodesic.mathdoc.fr/item/MZ_1923__16_174957/} }