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Sonne-Holm S, Sørensen TI.Sonne-Holm S, et al.Br Med J (Clin Res Ed). 1986 Mar 1;292(6520):586-9. doi: 10.1136/bmj.292.6520.586.Br Med J (Clin Res Ed). 1986.PMID: 3081178Free PMC article.