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Gehring U, Brunekreef B, Fahlbusch B, Wichmann HE, Heinrich J; INGA Study Group.Gehring U, et al. Among authors: brunekreef b.Allergy. 2005 Aug;60(8):1079-82. doi: 10.1111/j.1398-9995.2005.00872.x.Allergy. 2005.PMID: 15969691