@article{MM2_1998__95_3_156393,
     author = {Tatsuya Kawabe},
     title = {On the properly discontinuous subgroups of affine motions.},
     journal = {Manuscripta mathematica},
     pages = {529--544},
     publisher = {mathdoc},
     volume = {95},
     number = {3},
     year = {1998},
     zbl = {0899.22010},
     url = {http://geodesic.mathdoc.fr/item/MM2_1998__95_3_156393/}
}