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Vivanti G, Rogers SJ.Vivanti G, et al.Philos Trans R Soc Lond B Biol Sci. 2014 Apr 28;369(1644):20130184. doi: 10.1098/rstb.2013.0184. Print 2014.Philos Trans R Soc Lond B Biol Sci. 2014.PMID: 24778379Free PMC article.