@article{PulmanTimeAndModality,
  title = "Time and Modality in a Natural Language Interface to a Planning System",
  author = "R. S. Crouch and S. G. Pulman",
  year = "1993",
  journal = "Artificial Intelligence",
  note = "{This issue also reprinted as {\it Natural Language Processing}, ed. F. Pereira and B. Grosz, MIT Press, 1994}",
  pages = "265--304",
  volume = "63",
}