@article{ELMA_1946__1_140428,
     author = {Willi L\"ussy},
     title = {\"Aquipotentialkurven und ihre {Orthogonaltrajektorien.}},
     journal = {Elemente der Mathematik},
     pages = {25--31},
     publisher = {mathdoc},
     volume = {1},
     year = {1946},
     zbl = {0061.32204},
     url = {http://geodesic.mathdoc.fr/item/ELMA_1946__1_140428/}
}