@InProceedings{monz:07mode,
  author =       {Christof Monz},
  title =        {Model Tree Learning for Query Term Weighting in
                  Question Answering},
  booktitle = {Proceedings of the 29th Conference on Information Retrieval Research ({ECIR 2007}},
  pages =        {589--596},
  year =         2007,
  editor =       {G. Amati and C. Carpineto and G. Romano},
  series =       {LNCS 4425},
  publisher = {Springer}
}