@article{CRMATH_2002__335_10_785_0,
     author = {Baues, Oliver},
     title = {Finite extensions and unipotent shadows of affine crystallographic groups},
     journal = {Comptes Rendus. Math\'ematique},
     pages = {785--788},
     publisher = {Elsevier},
     volume = {335},
     number = {10},
     year = {2002},
     doi = {10.1016/S1631-073X(02)02562-1},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/S1631-073X(02)02562-1/}
}