@article{weko_59657_1,
   author	 = "Hitoshi,Iida and Hidekazu,Arita",
   title	 = "Natural Language Dialogue Understanding on a  Four-layer Plan Recognition Model",
   journal	 = "Journal of Information Processing ",
   year 	 = "1992",
   volume	 = "15",
   number	 = "1",
   pages	 = "60--71",
   month	 = "mar"
}