University of Massachusetts: Description of the CIRCUS System as Used for MUC-4 W Lehnert author C Cardie author D Fisher author J McCarthy author E Riloff author S Soderland author 1992 text Fourth Message Understanding Conference (MUC-4): Proceedings of a Conference Held in McLean, Virginia, June 16-18, 1992 conference publication lehnert-etal-1992-university-massachusetts https://aclanthology.org/M92-1038/ 1992