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Tsai Y, Sawaya MR, Cannon GC, Cai F, Williams EB, Heinhorst S, Kerfeld CA, Yeates TO.Tsai Y, et al. Among authors: kerfeld ca.PLoS Biol. 2007 Jun;5(6):e144. doi: 10.1371/journal.pbio.0050144.PLoS Biol. 2007.PMID: 17518518Free PMC article.