Yoshio Izumida Hiroshi Ishikawa Toshiaki Yoshino Tadashi Hoshiai Akifumi Makinouchi A Natural Language Interface Using A World Model. 205-212 1985 conf/eacl/1985 EACL http://acl.ldc.upenn.edu/E/E85/E85-1030.pdf db/conf/eacl/eacl1985.html#IzumidaIYHM85