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Vecht RJ, Nicolaides EP, Duffett A, Cumberland DC.Vecht RJ, et al.Br Med J (Clin Res Ed). 1987 Aug 8;295(6594):357-9. doi: 10.1136/bmj.295.6594.357.Br Med J (Clin Res Ed). 1987.PMID: 3115447Free PMC article.