@article{CMH_1933__5_138600,
     author = {Anna Fischer},
     title = {Grundlagen der elliptischen {Geometrie.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {246--253},
     year = {1933},
     volume = {5},
     zbl = {0006.31901},
     url = {http://geodesic.mathdoc.fr/item/CMH_1933__5_138600/}
}