The Classification Research Group (CRG) was a significant contributor to classification research and theory in the field of library and information science in the latter half of the 20th century. It was formed in England in 1952 and was active until 1968. Informal meetings continued until 1990. Among its members were Derek Austin, Eric Coates, Jason Farradane, Robert Fairthorne, Douglas Foskett, Barbara Kyle, Derek Langridge, Jack Mills, Pauline Atherton Cochrane, Bernard Palmer, Jack Wells, and Brian Campbell Vickery. The group formed important principles on faceted classification and also worked on the theory of integrative levels.
- 1955. The need for a faceted classification as the basis for all methods of information retrieval. Library Association Record, 57(7), 262-268.
- 1958. Classification Research Group Bulletin No. 4. Journal of Documentation, 14( 3), 136-143.
- 1959. Classification Research Group Bulletin No. 5. Journal of Documentation, 15(1), 39-57.
- 1961. Classification Research Group Bulletin No. 6. Journal of Documentation, 17(3), 156-172.
- 1962. Classification Research Group Bulletin No. 7. Journal of Documentation, 18( 2), 65-88.
- 1964. Classification Research Group Bulletin No. 8. Journal of Documentation, 20(3), 146-169.
- 1968. Classification Research Group Bulletin No. 9. Journal of Documentation, 24(4), 273-298.
- 1969. Classification and information control: Papers representing the work of the Classification Research Group during 1960-1968. London: Library Association.
- Foskett, D. J. (1971). "The Classification Research Group 1952-1968". In Kent, A.; Lancour, H. (eds.). Encyclopedia of Library and Information Science. Vol. 5. New York: Marcel Dekker. pp. 141–145.
- Hopkins, F. (1973). "General classification theory: a review of the CRG work". Library Resources and Technical Services. 17 (2): 201–210.
- Justice, A. (2004). "Information science as a facet of the history of British science: the origins of the Classification Research Group". In Rayward, B.; Bowden, M. E. (eds.). The History and Heritage of Scientific and Technological Information Systems. Medford, NJ: Information Today. CiteSeerX 10.1.1.163.7203.
- McIlwaine, I.; Broughton, V. (2000). "The Classification Research Group: then and now". Knowledge Organization. 27 (4): 195–199.
- Wilson, T. D. (1972). "The work of the British CRG". In Wellisch, H.; Wilson, T. D. (eds.). Subject Retrieval in the Seventies: New Directions. Proceedings of an International Symposium held at the Center of Adult Education, University of Maryland, College Park, May 14–15, 1971. Westport, Conn.: Greenwood. pp. 62–71.
- Spiteri, L. F. (1995). "The Classification Research Group and the Theory of Integrative Levels". Katharine Sharp Review. 1 (Summer 1995): 1–6. Archived from the original on 2001-12-22.
- Afolabi, M. (1985). A sociological study of the Classification Research Group. Library Science with a Slant to Documentation, 22(2), 77-85.
- Broughton, Vanda (2011). Brian Vickery and the Classification Research Group: the legacy of faceted classification. In Gilchrist, A. (Ed.) Proceedings of the Second National ISKO UK Conference 2011.
- Frohmann, Bernard P. (1983). An investigation of the semantic bases of some theoretical principles of classification proposed by Austin and the CRG. Cataloging and Classification Quarterly, 4(1), 11-27.