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Mortensen N, Savage A, Jones SM.Mortensen N, et al.Br Med J (Clin Res Ed). 1983 Apr 2;286(6371):1146. doi: 10.1136/bmj.286.6371.1146-a.Br Med J (Clin Res Ed). 1983.PMID: 6404364Free PMC article.No abstract available.