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Davis TM, Balme M, Jackson D, Stuccio G, Bruce DG. The diagonal ear lobe crease (Frank's sign) is not associated with coronary artery disease or retinopathy in type 2 diabetes: the Fremantle Diabetes Study. Aust N Z J Med. October 2000, 30 (5): 573–7. PMID 11108067. doi:10.1111/j.1445-5994.2000.tb00858.x.