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Pilling A, Davison AJ, Telford EA, Meredith DM.Pilling A, et al. Among authors: telford ea.J Gen Virol. 1994 Feb;75 ( Pt 2):439-42. doi: 10.1099/0022-1317-75-2-439.J Gen Virol. 1994.PMID: 8113768