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Freeman EE, White RG, Bakker R, Orroth KK, Weiss HA, Buvé A, Hayes RJ, Glynn JR.Freeman EE, et al. Among authors: orroth kk.Vaccine. 2009 Feb 5;27(6):940-6. doi: 10.1016/j.vaccine.2008.11.074. Epub 2008 Dec 9.Vaccine. 2009.PMID: 19071187Free PMC article.