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Watts GF, Lewis B, Brunt JN, Lewis ES, Coltart DJ, Smith LD, Mann JI, Swan AV.Watts GF, et al.Lancet. 1992 Mar 7;339(8793):563-9. doi: 10.1016/0140-6736(92)90863-x.Lancet. 1992.PMID: 1347091Clinical Trial.