@InProceedings{mehdad:2009:Short,
  author    = {Mehdad, Yashar},
  title     = {Automatic Cost Estimation for Tree Edit Distance Using Particle Swarm Optimization},
  booktitle = {Proceedings of the ACL-IJCNLP 2009 Conference Short Papers},
  month     = {August},
  year      = {2009},
  address   = {Suntec, Singapore},
  publisher = {Association for Computational Linguistics},
  pages     = {289--292},
  url       = {http://www.aclweb.org/anthology/P/P09/P09-2073}
}