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Visser JJ, Williams M, Kievit J, Bosch JL; 4-A Study Group.Visser JJ, et al.J Vasc Surg. 2009 May;49(5):1093-9. doi: 10.1016/j.jvs.2008.12.027.J Vasc Surg. 2009.PMID: 19394540Free article.