@ARTICLE{bmp09,
  author = {D. Bresolin and A. Montanari and G. Puppis},
  title = {A Theory of Ultimately Periodic Languages and Automata With an Application to Time Granularity},
  journal = {Acta Informatica},
  year = {2009},
  volume = {46},
  number = {5},
  pages = {331-360},
  publisher = {Springer}
}