@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},
     year = {1980},
     volume = {47},
     zbl = {0438.51002},
     url = {http://geodesic.mathdoc.fr/item/MS2_1980__47_166722/}
}