1. Appendix A: Tiling problems;Allauzen,1996
2. The undecidability of the domino problem;Berger;Mem. Am. Math. Soc.,1966
3. The Classical Decision Problem;Börger,1996
4. Description of the characteristic sequence of an irrational;Brown;Canad. Math. Bull.,1993
5. An aperiodic set of 13 Wang tiles;Cˇulik;Discrete Math.,1996