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Anderson HR, Ruggles R, Pandey KD, Kapetanakis V, Brunekreef B, Lai CK, Strachan DP, Weiland SK; ISAAC Phase One Study Group.Anderson HR, et al.Occup Environ Med. 2010 May;67(5):293-300. doi: 10.1136/oem.2009.048785. Epub 2009 Oct 9.Occup Environ Med. 2010.PMID: 19819866Clinical Trial.