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Cogswell JJ, Halliday DF, Alexander JR.Cogswell JJ, et al.Br Med J (Clin Res Ed). 1982 Apr 3;284(6321):1011-3. doi: 10.1136/bmj.284.6321.1011.Br Med J (Clin Res Ed). 1982.PMID: 6802386Free PMC article.