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Collard HR, Ryu JH, Douglas WW, Schwarz MI, Curran-Everett D, King TE Jr, Brown KK.Collard HR, et al. Among authors: ryu jh.Chest. 2004 Jun;125(6):2169-74. doi: 10.1378/chest.125.6.2169.Chest. 2004.PMID: 15189938