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Woelk CH, Pybus OG, Jin L, Brown DWG, Holmes EC.Woelk CH, et al. Among authors: pybus og.J Gen Virol. 2002 Jun;83(Pt 6):1419-1430. doi: 10.1099/0022-1317-83-6-1419.J Gen Virol. 2002.PMID: 12029157