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Pentikainen PJ, Neuvonen PJ, Tarpila S, Syvälahti E.Pentikainen PJ, et al.Br Med J. 1978 Sep 23;2(6141):861-3. doi: 10.1136/bmj.2.6141.861.Br Med J. 1978.PMID: 709096Free PMC article.