A major figure of the InformationRetrieval community. He is the leader of the GlasgowInformationRetrievalGroup based at GlasgowUniversity. Wrote the seminal book Information Retrieval that is now available online from this web site:
http://www.dcs.gla.ac.uk/Keith/Preface.html. Recently wrote the classic The Geometery of Information Retrieval textbook
http://ir.dcs.gla.ac.uk/GeometryOfIR/.
Other academic members of the Glasgow Information Retrieval group include IadhOunis and JoemonJose.
Glasgow Information Retrieval Group
Information Retrieval book - C. J. van Rijsbergen 1979