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Chappell J, Hawes N.Chappell J, et al.Philos Trans R Soc Lond B Biol Sci. 2012 Oct 5;367(1603):2723-32. doi: 10.1098/rstb.2012.0221.Philos Trans R Soc Lond B Biol Sci. 2012.PMID: 22927571Free PMC article.Review.