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Campbell DE, Tustin NB, Riedel E, Tustin R 3rd, Taylor J, Murray J, Douglas SD.Campbell DE, et al.Clin Vaccine Immunol. 2009 Nov;16(11):1648-53. doi: 10.1128/CVI.00259-09. Epub 2009 Sep 2.Clin Vaccine Immunol. 2009.PMID: 19726615Free PMC article.