@article{JRAM_1976__285_151759,
     author = {Dieter Betten},
     title = {4-dimensionale {Translationsebenen} mit 7-dimensionaler {Kollineationsgruppe.}},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {126--148},
     publisher = {mathdoc},
     volume = {285},
     year = {1976},
     zbl = {0326.50013},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1976__285_151759/}
}