Palindromic factors of billiard words

@article{Borel2005PalindromicFO,
  title={Palindromic factors of billiard words},
  author={Jean-Pierre Borel and Christophe Reutenauer},
  journal={Theor. Comput. Sci.},
  year={2005},
  volume={340},
  pages={334-348}
}