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Ryder RW, Reeves WC, Singh N, Hall CB, Kapikian AZ, Gomez B, Sack RB.Ryder RW, et al. Among authors: sack rb.Am J Trop Med Hyg. 1985 Sep;34(5):921-4. doi: 10.4269/ajtmh.1985.34.921.Am J Trop Med Hyg. 1985.PMID: 4037183