@article{MAN_1933__107_159603,
     author = {G. Scheffers},
     title = {Schnitte, {Umrisse} und {Schatten} der {Fl\"achen} einer {Fl\"achenfamilie}},
     journal = {Mathematische Annalen},
     pages = {467--470},
     publisher = {mathdoc},
     volume = {107},
     year = {1933},
     zbl = {58.0739.06},
     url = {http://geodesic.mathdoc.fr/item/MAN_1933__107_159603/}
}