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Petersen MB, Pedersen SA, Greisen G, Pedersen JF, Mølsted-Pedersen L.Petersen MB, et al.Br Med J (Clin Res Ed). 1988 Feb 27;296(6622):598-600. doi: 10.1136/bmj.296.6622.598.Br Med J (Clin Res Ed). 1988.PMID: 2450619Free PMC article.