[1] G. K. Zipf. 1949. Human behaviour and the principle of least effort: An introduction to human ecology. (Hafner reprint, New York, 1972), 1st edition: Cambridge, MA: AddisonWesley, 1949.

[2] W. Li, Zipf's law, http://linkage.rockefeller.edu/wli/zipf, WWW.

[3] J. L. Casti, Complexity 1, (1995).

[4] W. Li, Complexity 3, 9 (1998), comments to "Zipf's Law and the structure and evolution of languages" A.A. Tsonis, C. Schultz, P.A. Tsonis, COMPLEXITY, 2(5). 12-13 (1997).

[5] M. A. Nowak, J. B. Plotkin, and V. A. Jansen, The evolution of syntactic communication. Nature 495 (2000).

[6] A. A. Tsonis, C. Schultz, and P. A. Tsonis, (1997). Zipf's Law and the structure and evolution of languages. Complexity 3, (1997).

[7] W. Ebeling and T. Poschel, Europhysics Letters 26, 241 (1994).

[8] R. Ferrer and R. V. Sole, To be submited to Europhysics Letters (2000).

[9] S. Romaine, in The Evolution of Human Languages, edited by J. A. Hawkins and M. Gell-Mann (Addison Wesley, ADDRESS, 1992), pp. 213-238.

[10] S. Romaine, Pidgin and Creole Languages (Longman, London, 1988).

[11] R. A. Hall, 1953. Haitian Creole: Grammar, Texts, Vocabulary (American Folcklore Society Memoire, ADDRESS, 1953), No. 43.