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Woods RL, Fox RM, Tattersall MH.Woods RL, et al. Among authors: tattersall mh.Br Med J (Clin Res Ed). 1981 Feb 21;282(6264):600-2. doi: 10.1136/bmj.282.6264.600.Br Med J (Clin Res Ed). 1981.PMID: 6781586Free PMC article.Clinical Trial.