USC: Description of the SNAP System Used for MUC-4 D Moldovan author S Chet author M Chung author K Hendrickson author J Kim author S Kowalski author 1992 text Fourth Message Understanding Conference (MUC-4): Proceedings of a Conference Held in McLean, Virginia, June 16-18, 1992 conference publication moldovan-etal-1992-usc-description https://aclanthology.org/M92-1040/ 1992