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Revilla Y, Pena L, Mampaso F, Viñuela E, Martinez-Alonso C.Revilla Y, et al.J Gen Virol. 1994 Aug;75 ( Pt 8):1983-8. doi: 10.1099/0022-1317-75-8-1983.J Gen Virol. 1994.PMID: 8046401