1. Bywaters, E. G. L., and Dresner, E. (1952). Quart. J. Med., 21, 463.
2. Report on an enquiry into the aetiological factors associated with rheumatoid arthritis;Duthie, J.J.R.;Practitioner; Empire Rheumatism Council,1951
3. Jeffrey, M. R. (1952). Annals of the Rheumatic Diseases, 11, 162.
4. Jeffrey, M. R. (1953). Blood, 8, 502. Medical Research Council and Nuffield Foundation Joint Report (1954). Brit. med. J., 1, 1223. Ragan, C. (1949). J. Amer. med. Ass., 141, 124.
5. Ragan, C. (1951). Bull. N.Y. Acad. Med., 27, 63.