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Winkelstein W Jr, Wiley JA, Padian NS, Samuel M, Shiboski S, Ascher MS, Levy JA.Winkelstein W Jr, et al.Am J Public Health. 1988 Nov;78(11):1472-4. doi: 10.2105/ajph.78.11.1472.Am J Public Health. 1988.PMID: 3177723Free PMC article.