@inproceedings{Lemon-etAl:2003:SIGDIAL,
  author = {Lemon, Oliver  and  Cavedon, Lawrence  and  Kelly, Barbara},
  title = {Managing Dialogue Interaction: A Multi-Layered Approach},
  booktitle = {Proceedings of the Fourth {SIGdial} Workshop on Discourse and Dialogue},
  editor = {Akira Kurematsu and Alexander Rudnicky and Syun Tutiya},
  url = {http://www.aclweb.org/anthology/W03-2114},
  year = 2003,
  pages = {168--177}