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Jelnes R, Gaardsting O, Hougaard Jensen K, Baekgaard N, Tønnesen KH, Schroeder T.Jelnes R, et al.Br Med J (Clin Res Ed). 1986 Nov 1;293(6555):1137-40. doi: 10.1136/bmj.293.6555.1137.Br Med J (Clin Res Ed). 1986.PMID: 3094806Free PMC article.