@inproceedings{schlangen:2004:SIGDIAL,
  author    = {Schlangen, David},
  title     = {Causes and Strategies for Requesting Clarification in Dialogue},
  booktitle = {Proceedings of the 5th SIGdial Workshop on Discourse and Dialogue },
  editor = {Michael Strube and Candy Sidner},
  year      = 2004,
  month     = {April 30 - May 1},
  address   = {Cambridge, Massachusetts, USA},
  publisher = {Association for Computational Linguistics},
  pages     = {136--143}
}