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Palmer KR, Goepel JR, Holdsworth CD.Palmer KR, et al.Br Med J (Clin Res Ed). 1981 May 16;282(6276):1571-3. doi: 10.1136/bmj.282.6276.1571.Br Med J (Clin Res Ed). 1981.PMID: 6113021Free PMC article.Clinical Trial.