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Naumann RB, Marshall SW, Lund JL, Skinner AC, Ringwalt C, Gottfredson NC.Naumann RB, et al. Among authors: gottfredson nc.N C Med J. 2019 May-Jun;80(3):135-142. doi: 10.18043/ncm.80.3.135.N C Med J. 2019.PMID: 31072939Free PMC article.