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Welch SG, McGregor IA, Williams K.Welch SG, et al. Among authors: mcgregor ia.Trans R Soc Trop Med Hyg. 1977;71(4):295-6. doi: 10.1016/0035-9203(77)90102-x.Trans R Soc Trop Med Hyg. 1977.PMID: 339418
McGregor IA, Williams K, Walker GH, Rahman AK.McGregor IA, et al.Br Med J. 1966 Mar 19;1(5489):695-701. doi: 10.1136/bmj.1.5489.695.Br Med J. 1966.PMID: 5909480Free PMC article.Clinical Trial.No abstract available.