An expert system for bibliographic retrieval using Prolog. - Carolyn R. Watters; Michael A. Shepherd; W. Robertson; K. H. Lee (ACM Conference on Computer Science, 1987)

Towards an Expert System for Bibliographic Retrieval: A Prolog Prototype. - Carolyn R. Watters; Michael A. Shepherd; W. Robertson (SIGIR, 1987)

A neural algorithm for document clustering. - Kevin J. Macleod; W. Robertson (Inf. Process. Manag., 1991)