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Tappero JW, Mohle-Boetani J, Koehler JE, Swaminathan B, Berger TG, LeBoit PE, Smith LL, Wenger JD, Pinner RW, Kemper CA, et al.Tappero JW, et al.JAMA. 1993 Feb 10;269(6):770-5.JAMA. 1993.PMID: 8423659