@INPROCEEDINGS{dmp03,
  author = {U. {Dal Lago} and A. Montanari and G. Puppis},
  title = {Towards Compact and Tractable Automaton-based Representations of Time Granularity},
  booktitle = {Proceedings of the 8th Italian Conference on Theoretical Computer Science (ICTCS)},
  year = {2003},
  volume = {2841},
  series = {LNCS},
  pages = {72-85},
  publisher = {Springer}
}