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Chadd MA, Elwood PC, Gray OP, Muxworthy SM.Chadd MA, et al.Br Med J. 1972 Jan 29;1(5795):309. doi: 10.1136/bmj.1.5795.309-b.Br Med J. 1972.PMID: 5008487Free PMC article.No abstract available.
Chadd MA, Elwood PC, Gray OP, Muxworthy SM.Chadd MA, et al.Br Med J. 1971 Nov 27;4(5786):516-8. doi: 10.1136/bmj.4.5786.516.Br Med J. 1971.PMID: 5126955Free PMC article.