EP-X: A Knowledge-Based System to Aid in Searches of the Environmental Pollution Literature. - Deb A. Krawczak; Philip J. Smith; Steven J. Shute; Mark H. Chignell (CAIA, 1985)

EP-X: A Demonstration of Semantically-Based Search of Bibliographic Databases. - Deb A. Krawczak; Philip J. Smith; Steven J. Shute (SIGIR, 1987)