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de Boer PT, Pouwels KB, Cox JM, Hak E, Wilschut JC, Postma MJ.de Boer PT, et al.Vaccine. 2013 Feb 18;31(9):1276-83. doi: 10.1016/j.vaccine.2012.12.067. Epub 2013 Jan 8.Vaccine. 2013.PMID: 23306360