@InProceedings{morita-sakai-okumura:2011:ACL-HLT2011,
  author    = {Morita, Hajime  and  Sakai, Tetsuya  and  Okumura, Manabu},
  title     = {Query Snowball: A Co-occurrence-based Approach to Multi-document Summarization for Question Answering},
  booktitle = {Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies},
  month     = {June},
  year      = {2011},
  address   = {Portland, Oregon, USA},
  publisher = {Association for Computational Linguistics},
  pages     = {223--229},
  url       = {http://www.aclweb.org/anthology/P11-2039}
}