@article{CMH_1939__12_138750,
     author = {Paul Finsler},
     title = {Die eindimensionalen {Freigebilde.}},
     journal = {Commentarii mathematici Helvetici},
     pages = {254--262},
     year = {1939},
     volume = {12},
     zbl = {0023.16001},
     url = {http://geodesic.mathdoc.fr/item/CMH_1939__12_138750/}
}