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Barr RG, Woodruff PG, Clark S, Camargo CA Jr.Barr RG, et al. Among authors: woodruff pg.Eur Respir J. 2000 Feb;15(2):266-73. doi: 10.1034/j.1399-3003.2000.15b08.x.Eur Respir J. 2000.PMID: 10706490Free article.