@inproceedings{Zens:2003:ACL,
  author = {Zens, Richard  and  Ney, Hermann},
  title  = {A Comparative Study on Reordering Constraints in Statistical Machine Translation},
  booktitle = {Proceedings of the 41st Annual Meeting of the Association for Computational Linguistics},
  editor = {Erhard Hinrichs and Dan Roth},
  url    = {http://www.aclweb.org/anthology/P03-1019.pdf},
  year   = 2003,
  pages  = {144--151}
}