McDonnell Douglas Electronic Systems Company MUC-4 Test Results and Analysis Amnon Meyers author David de Hilster author 1992 text Fourth Message Understanding Conference (MUC-4): Proceedings of a Conference Held in McLean, Virginia, June 16-18, 1992 conference publication meyers-de-hilster-1992-mcdonnell https://aclanthology.org/M92-1012/ 1992