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Perley CC, Frahm M, Click EM, Dobos KM, Ferrari G, Stout JE, Frothingham R.Perley CC, et al. Among authors: frothingham r.PLoS One. 2014 Jun 11;9(2):e98938. doi: 10.1371/journal.pone.0098938. eCollection 2014.PLoS One. 2014.PMID: 24918450Free PMC article.