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Schonlau M, Scribner R, Farley TA, Theall K, Bluthenthal RN, Scott M, Cohen DA.Schonlau M, et al.Geospat Health. 2008 Nov;3(1):91-101. doi: 10.4081/gh.2008.235.Geospat Health. 2008.PMID: 19021112Free PMC article.