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Zhang S, Hunter DJ, Forman MR, Rosner BA, Speizer FE, Colditz GA, Manson JE, Hankinson SE, Willett WC.Zhang S, et al.J Natl Cancer Inst. 1999 Mar 17;91(6):547-56. doi: 10.1093/jnci/91.6.547.J Natl Cancer Inst. 1999.PMID: 10088626