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Bockman DE, Black O Jr, Mills LR, Mainz DL, Webster PD 3rd.Bockman DE, et al. Among authors: mainz dl.J Natl Cancer Inst. 1976 Oct;57(4):931-6. doi: 10.1093/jnci/57.4.931.J Natl Cancer Inst. 1976.PMID: 187782