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De Zoysa AP, Mendis C, Gamage-Mendis AC, Weerasinghe S, Herath PR, Mendis KN.De Zoysa AP, et al. Among authors: mendis kn, mendis c.Bull World Health Organ. 1991;69(6):725-34.Bull World Health Organ. 1991.PMID: 1786621Free PMC article.