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Weil J, Colin-Jones D, Langman M, Lawson D, Logan R, Murphy M, Rawlins M, Vessey M, Wainwright P.Weil J, et al.BMJ. 1995 Apr 1;310(6983):827-30. doi: 10.1136/bmj.310.6983.827.BMJ. 1995.PMID: 7711618Free PMC article.