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Siegal HA, Carlson RG, Falck R, Li L, Forney MA, Rapp RC, Baumgartner K, Myers W, Nelson M.Siegal HA, et al. Among authors: carlson rg.Am J Public Health. 1991 Dec;81(12):1642-4. doi: 10.2105/ajph.81.12.1642.Am J Public Health. 1991.PMID: 1746663Free PMC article.