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Campbell AN, Tross S, Dworkin SL, Hu MC, Manuel J, Pavlicova M, Nunes EV.Campbell AN, et al. Among authors: dworkin sl.J Urban Health. 2009 Nov;86(6):951-64. doi: 10.1007/s11524-009-9405-0.J Urban Health. 2009.PMID: 19921541Free PMC article.