BBN HARC and DELPHI Results on the ATIS Benchmarks - February 1991 S Austin author D Ayuso author M Bates author R Bobrow author R Ingria author J Makhoul author P Placeway author R Schwartz author D Stallard author 1991 text Speech and Natural Language: Proceedings of a Workshop Held at Pacific Grove, California, February 19-22, 1991 conference publication austin-etal-1991-bbn https://aclanthology.org/H91-1018/ 1991