@article{MZ_1968__107_171071,
     author = {F.D. Veldkamp and T.A. Springer},
     title = {On {Hjelmslev-Moufang} {Planes.}},
     journal = {Mathematische Zeitschrift},
     pages = {249--263},
     publisher = {mathdoc},
     volume = {107},
     year = {1968},
     zbl = {0164.51301},
     url = {http://geodesic.mathdoc.fr/item/MZ_1968__107_171071/}
}