@article{MS2_1980__47_166722, author = {Sten Hansen}, title = {On configurations in 3-space without elementary planes and on the number of ordinary planes.}, journal = {Mathematica Scandinavica}, pages = {181--194}, publisher = {mathdoc}, volume = {47}, year = {1980}, zbl = {0438.51002}, url = {http://geodesic.mathdoc.fr/item/MS2_1980__47_166722/} }