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Farrington CP, Firth MJ, Moulton LH, Ravn H, Andersen PK, Evans S; Working Group on Non-specific Effects of Vaccines.Farrington CP, et al. Among authors: firth mj.Trop Med Int Health. 2009 Sep;14(9):977-85. doi: 10.1111/j.1365-3156.2009.02302.x. Epub 2009 Jun 15.Trop Med Int Health. 2009.PMID: 19531116Free article.Review.