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Crouch AA, Seow WK, Whitman LM, Smith SE, Thong YH.Crouch AA, et al. Among authors: seow wk.Trans R Soc Trop Med Hyg. 1991 May-Jun;85(3):375-9. doi: 10.1016/0035-9203(91)90297-c.Trans R Soc Trop Med Hyg. 1991.PMID: 1949142