@article{MZ_1959__71_169804,
     author = {Joachim Ahrens},
     title = {Begr\"undung der absoluten {Geometrie} des {Raumes} aus dem {Spiegelungsbegriff.}},
     journal = {Mathematische Zeitschrift},
     pages = {154--185},
     publisher = {mathdoc},
     volume = {71},
     year = {1959},
     zbl = {0088.37003},
     url = {http://geodesic.mathdoc.fr/item/MZ_1959__71_169804/}
}