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Robertson SE, Roca A, Alonso P, Simoes EA, Kartasasmita CB, Olaleye DO, Odaibo GN, Collinson M, Venter M, Zhu Y, Wright PF.Robertson SE, et al.Bull World Health Organ. 2004 Dec;82(12):914-22. Epub 2005 Jan 5.Bull World Health Organ. 2004.PMID: 15654405Free PMC article.