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Lundback B, Alexander M, Day J, Hebert J, Holzer R, Van Uffelen R, Kesten S, Jones AL.Lundback B, et al. Among authors: day j.Respir Med. 1993 Nov;87(8):609-20. doi: 10.1016/s0954-6111(05)80264-1.Respir Med. 1993.PMID: 8290745Clinical Trial.