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Nelson DR, Goldstone JV, Stegeman JJ.Nelson DR, et al. Among authors: stegeman jj.Philos Trans R Soc Lond B Biol Sci. 2013 Jan 6;368(1612):20120474. doi: 10.1098/rstb.2012.0474. Print 2013 Feb 19.Philos Trans R Soc Lond B Biol Sci. 2013.PMID: 23297357Free PMC article.