1. Automatic Sequences;Allouche,2003
2. Avoidable patterns in strings of symbols;Bean;Pacific J. Math,1979
3. J. Berstel, Axel Thue's work on repetition in words, Technical Report 92.70, LITP, September 1992, 4th Conference on Formal Power Series and Algebraic Combinatorics, Montréal, 1992.
4. J. Berstel, Axel Thue's papers on repetition in words: a translation, Technical Report 20, Laboratoire de Combinatoire et d’Informatique Mathématique, Université du Québec, Montréal, 1995.
5. Growth of repetition-free words—a review;Berstel;Theoret. Comput. Sci.,2005