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Feldman C, Anderson R, Theron AJ, Steel HC, van Rensburg CE, Cole PJ, Wilson R.Feldman C, et al. Among authors: steel hc.Eur Respir J. 2001 Jul;18(1):122-9. doi: 10.1183/09031936.01.00037401.Eur Respir J. 2001.PMID: 11510782Free article.