@article{AM2_1987__32_137191,
     author = {Helmut M\"aurer},
     title = {Die affine {Projektivit\"atengruppe} der {Hallebenen.}},
     journal = {Aequationes mathematicae},
     pages = {271--273},
     publisher = {mathdoc},
     volume = {32},
     year = {1987},
     url = {http://geodesic.mathdoc.fr/item/AM2_1987__32_137191/}
}