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Dawson AH, Harvey D, Smith AJ, Taylor M, Whyte IM, Johnson CI, Cubela RB, Roberts MJ.Dawson AH, et al.Lancet. 1990 Feb 24;335(8687):487-8. doi: 10.1016/0140-6736(90)90731-j.Lancet. 1990.PMID: 1968218No abstract available.