%0 Journal Article %A Stefan Breulmann %A Volker Helmke %T The covolume of quaternion groups on the four-dimensional hyperbolic space %J Acta Arithmetica %D 1996 %P 9-21 %V 77 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/aa-77-1-9-21/ %R 10.4064/aa-77-1-9-21 %G en %F 10_4064_aa_77_1_9_21