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Hahn RA, Magder LS, Aral SO, Johnson RE, Larsen SA.Hahn RA, et al. Among authors: aral so.Am J Public Health. 1989 Apr;79(4):467-70. doi: 10.2105/ajph.79.4.467.Am J Public Health. 1989.PMID: 2929806Free PMC article.
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