1. H. Brown, R. B low, J. Neub ser, H. Wondratscheck and H. Zassenhaus. Crystallographic groups of four-dimensional space (Wiley-Interscience, 1978).
2. CARAT Crystallographic AlgoRithms And Tables, version 1.2 (Lehrstuhl B fur Mathematik, Aachen, 2001) http://wwwb.math.rwth-aachen.de/carat/.
3. Compact Flat Riemannian Manifolds III: The Group of Affinities
4. Computation of Five-and Six-Dimensional Bieberbach Groups