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Piette JD, Lun KC, Moura LA Jr, Fraser HS, Mechael PN, Powell J, Khoja SR.Piette JD, et al.Bull World Health Organ. 2012 May 1;90(5):365-72. doi: 10.2471/BLT.11.099069.Bull World Health Organ. 2012.PMID: 22589570Free PMC article.Review.