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Welch D, Fremaux G.Welch D, et al.Int J Environ Res Public Health. 2017 Aug 11;14(8):908. doi: 10.3390/ijerph14080908.Int J Environ Res Public Health. 2017.PMID: 28800097Free PMC article.
John GW, Grynevych A, Welch D, McBride D, Thorne PR.John GW, et al. Among authors: welch d.Arch Environ Occup Health. 2014;69(2):69-80. doi: 10.1080/19338244.2012.732122.Arch Environ Occup Health. 2014.PMID: 24205958