@Book{tutorial:2007,
  editor    = {Marti Hearst  and  Gina-Anne Levow  and  James Allan},
  title     = {Proceedings of the Human Language Technology Conference of the NAACL, Companion Volume: Tutorial Abstracts},
  month     = {April},
  year      = {2007},
  address   = {Rochester, New York},
  publisher = {Association for Computational Linguistics},
  url       = {http://www.aclweb.org/anthology/N/N07/N07-5}
}