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Chapman JD, McPhee MS, Walz N, Chetner MP, Stobbe CC, Soderlind K, Arnfield M, Meeker BE, Trimble L, Allen PS.Chapman JD, et al.J Natl Cancer Inst. 1991 Nov 20;83(22):1650-9. doi: 10.1093/jnci/83.22.1650.J Natl Cancer Inst. 1991.PMID: 1749018