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Fitchett JR, Head MG, Atun R.Fitchett JR, et al. Among authors: head mg.Vaccine. 2013 Dec 5;31(50):5930-3. doi: 10.1016/j.vaccine.2013.10.048. Epub 2013 Oct 25.Vaccine. 2013.PMID: 24176489Free article.