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Webby RJ, Webster RG.Webby RJ, et al. Among authors: webster rg.Philos Trans R Soc Lond B Biol Sci. 2001 Dec 29;356(1416):1817-28. doi: 10.1098/rstb.2001.0997.Philos Trans R Soc Lond B Biol Sci. 2001.PMID: 11779380Free PMC article.Review.