@InProceedings{ristad-thomas:1997:ACL,
  author    = {Eric Sven Ristad  and  Robert G. Thomas},
  title     = {Hierarchical Non-Emitting Markov Models},
  booktitle = {Proceedings of the 35th Annual Meeting of the Association for Computational Linguistics},
  month     = {July},
  year      = {1997},
  address   = {Madrid, Spain},
  publisher = {Association for Computational Linguistics},
  pages     = {381--385},
  url       = {http://www.aclweb.org/anthology/P97-1049},
  doi       = {10.3115/976909.979666}
}