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Sardinha A, Freire RC, Zin WA, Nardi AE.Sardinha A, et al. Among authors: nardi ae.J Bras Pneumol. 2009 Jul;35(7):698-708. doi: 10.1590/s1806-37132009000700012.J Bras Pneumol. 2009.PMID: 19669009Free article.Review.English, Portuguese.