@article{GDZPPN00239748X, title = {Collineation Groups Containing Elations. II.}, journal = {Mathematische Zeitschrift}, volume = {93}, year = {1966}, pages = {281-287}, zbl = {0158.19406}, url = {http://dml.mathdoc.fr/item/GDZPPN00239748X} }
Piper, F.C. Collineation Groups Containing Elations. II.. Mathematische Zeitschrift, Tome 93 (1966) pp. 281-287. http://gdmltest.u-ga.fr/item/GDZPPN00239748X/