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Liu Y, Croft JB, Anderson LA, Wheaton AG, Presley-Cantrell LR, Ford ES.Liu Y, et al. Among authors: croft jb.Int J Chron Obstruct Pulmon Dis. 2014 Jan 15;9:75-83. doi: 10.2147/COPD.S53676. eCollection 2014.Int J Chron Obstruct Pulmon Dis. 2014.PMID: 24477269Free PMC article.