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Edmunds WJ, Medley GF, Nokes DJ.Edmunds WJ, et al.Trans R Soc Trop Med Hyg. 1996 Jul-Aug;90(4):436-40. doi: 10.1016/s0035-9203(96)90539-8.Trans R Soc Trop Med Hyg. 1996.PMID: 8882200