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Barnett E, Halverson J.Barnett E, et al.Am J Public Health. 2001 Sep;91(9):1499-506. doi: 10.2105/ajph.91.9.1499.Am J Public Health. 2001.PMID: 11527788Free PMC article.
Barnett E, Armstrong DL, Casper ML.Barnett E, et al.Am J Public Health. 1997 Sep;87(9):1521-5. doi: 10.2105/ajph.87.9.1521.Am J Public Health. 1997.PMID: 9314808Free PMC article.
Barnett E, Strogatz D, Armstrong D, Wing S.Barnett E, et al.J Epidemiol Community Health. 1996 Jun;50(3):252-7. doi: 10.1136/jech.50.3.252.J Epidemiol Community Health. 1996.PMID: 8935454Free PMC article.