1. Die Bewegungsgruppen der Kristallographie;Burckhardt,1966
2. Generators and Relations for Discrete Groups;Coxeter,1972
3. The Graphic Work of M.C. Escher;Escher,1960
4. The eighty-one types of isohedral tilings of the plane;Grünbaum;Math. Proc. Cambridge Philos. Soc.,1977
5. The Costume and Textile Ornament of the Pre-Inca Cultures;Izumi,1964