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van Driel PW, Robertson WD, Merkley LC.van Driel PW, et al. Among authors: robertson wd.J Environ Qual. 2006 Feb 2;35(2):412-20. doi: 10.2134/jeq2005.0027. Print 2006 Mar-Apr.J Environ Qual. 2006.PMID: 16455841