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Tsarev SA, Tsareva TS, Emerson SU, Govindarajan S, Shapiro M, Gerin JL, Purcell RH.Tsarev SA, et al. Among authors: purcell rh.Vaccine. 1997 Dec;15(17-18):1834-8. doi: 10.1016/s0264-410x(97)00145-x.Vaccine. 1997.PMID: 9413090Free article.