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Poulos LM, Ampon RD, Marks GB, Reddel HK.Poulos LM, et al.Prim Care Respir J. 2013 Jun;22(2):201-8. doi: 10.4104/pcrj.2013.00036.Prim Care Respir J. 2013.PMID: 23616052Free PMC article.