@article{MAN_1956__131_160493,
     author = {G. Ewald},
     title = {Axiomatischer {Aufbau} der {Kreisgeometrie.}},
     journal = {Mathematische Annalen},
     pages = {354--371},
     publisher = {mathdoc},
     volume = {131},
     year = {1956},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MAN_1956__131_160493/}
}