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English DR, Armstrong BK.English DR, et al. Among authors: armstrong bk.Br Med J (Clin Res Ed). 1988 May 7;296(6632):1285-8. doi: 10.1136/bmj.296.6632.1285.Br Med J (Clin Res Ed). 1988.PMID: 3133052Free PMC article.