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Giovannucci E, Stampfer MJ, Colditz G, Rimm EB, Willett WC.Giovannucci E, et al.J Natl Cancer Inst. 1992 Jan 15;84(2):91-8. doi: 10.1093/jnci/84.2.91.J Natl Cancer Inst. 1992.PMID: 1310511