@article{MZ_1937__42_168711,
     author = {U., Graf},
     title = {Zur {Liniengeometrie} im linearen {Strahlenkomplex} und zur {Laguerreschen} {Kugelgeometrie}},
     journal = {Mathematische Zeitschrift},
     pages = {189--202},
     publisher = {mathdoc},
     volume = {42},
     year = {1937},
     zbl = {0015.36702},
     url = {http://geodesic.mathdoc.fr/item/MZ_1937__42_168711/}
}