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Merkus PJ, van Essen-Zandvliet EE, Parlevliet E, Borsboom G, Sterk PJ, Kerrebijn KF, Quanjer PH.Merkus PJ, et al. Among authors: sterk pj.Eur Respir J. 1992 Apr;5(4):488-91.Eur Respir J. 1992.PMID: 1563507