1. R. M. May,Nature 261:495 (1976).
2. M. Feigenbaum,J. Stat. Phys. 19:25 (1978);21:669 (1979).
3. P. Bak,Phys. Rev. Lett. 46:791 (1981).
4. S. Aubry, inSolitons in Condensed Matter Physics, A. R. Bishop and T. Schneider, eds. (Springer Verlag, New York, 1978).
5. P. Collet and J.-P. Eckman,Iterated Maps on the Interval as Dynamical Systems (Birkhauser, Boston, 1980).