1. E. Altman, B. Gaujal, A. Hordijk, Admission control in stochastic event graphs, Report TW-97-06, Leiden University, November 1997.
2. Two-dimensional periodicity in rectangular arrays;Amir;SIAM J. Comput.,1998
3. Rauzy's conjecture on billards in the cube;Arnoux;Tokyo J. Math.,1994
4. Complexity of trajectories in rectangular billards;Baryshnikow;Comm. Math. Phys.,1995
5. J. Berstel, Recent results in Sturmian words, in: Dassow, Rozenberg, Salomaa (Eds.), Developments in Language Theory II, World Scientific, Singapore, 1996, pp. 13–24.