@article{MOMA_1948__52_176799,
     author = {Erwin Kruppa},
     title = {Strahlfl\"achen als {Verallgemeinerungen} der {Ces;ro-Kurven.}},
     journal = {Monatshefte f\"ur Mathematik},
     pages = {323--336},
     publisher = {mathdoc},
     volume = {52},
     year = {1948},
     zbl = {0031.26901},
     url = {http://geodesic.mathdoc.fr/item/MOMA_1948__52_176799/}
}