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Crawford TV, McGrowder DA, Crawford A.Crawford TV, et al.N Am J Med Sci. 2009 Oct;1(5):247-55. doi: 10.4297/najms.2009.5247.N Am J Med Sci. 2009.PMID: 22666704Free PMC article.
McGrowder DA, Jackson LA, Crawford TV.McGrowder DA, et al.Asian Pac J Cancer Prev. 2012;13(1):1-13. doi: 10.7314/apjcp.2012.13.1.001.Asian Pac J Cancer Prev. 2012.PMID: 22502649Free article.Review.