%0 Journal Article %A Karel Dekimpe %T Units in group rings of crystallographic groups %J Fundamenta Mathematicae %D 2003 %P 169-178 %V 179 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/fm179-2-4/ %R 10.4064/fm179-2-4 %G en %F 10_4064_fm179_2_4