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Simons BD, Morrison AS, Lev R, Verhoek-Oftedahl W.Simons BD, et al. Among authors: morrison as.J Natl Cancer Inst. 1992 Jun 17;84(12):962-6. doi: 10.1093/jnci/84.12.962.J Natl Cancer Inst. 1992.PMID: 1629917