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Hudson RR, Kaplan NL.Hudson RR, et al.Philos Trans R Soc Lond B Biol Sci. 1995 Jul 29;349(1327):19-23. doi: 10.1098/rstb.1995.0086.Philos Trans R Soc Lond B Biol Sci. 1995.PMID: 8748015