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Angel E, Yaghmai N, Jude CM, Demarco JJ, Cagnon CH, Goldin JG, Primak AN, Stevens DM, Cody DD, McCollough CH, McNitt-Gray MF.Angel E, et al. Among authors: mccollough ch.Phys Med Biol. 2009 Feb 7;54(3):497-512. doi: 10.1088/0031-9155/54/3/003. Epub 2009 Jan 6.Phys Med Biol. 2009.PMID: 19124953Free PMC article.