@InProceedings{zhu-EtAl:2008:ACLMain,
  author    = {Zhu, Xiaojin  and  Goldberg, Andrew B.  and  Rabbat, Michael  and  Nowak, Robert},
  title     = {Learning Bigrams from Unigrams},
  booktitle = {Proceedings of ACL-08: HLT},
  month     = {June},
  year      = {2008},
  address   = {Columbus, Ohio},
  publisher = {Association for Computational Linguistics},
  pages     = {656--664},
  url       = {http://www.aclweb.org/anthology/P/P08/P08-1075}
}