@article{MZ_1921__9_167615,
     author = {E., Salkowski},
     title = {Orthogonale {Korvensysteme} in der {Ebene} und auf der {Kugel}},
     journal = {Mathematische Zeitschrift},
     pages = {136--141},
     publisher = {mathdoc},
     volume = {9},
     year = {1921},
     zbl = {48.0809.01},
     url = {http://geodesic.mathdoc.fr/item/MZ_1921__9_167615/}
}