Rieber J, Sheth TN, Mooyaart EA, Shapiro MD, Butler J, Ferencik M, Brady TJ, Klauss V, Hoffmann U. Assessment of the presence and extent of coronary collateralization by coronary computed tomographic angiography in patients with total occlusions. Int J Cardiovasc Imaging. 2009 Mar; 25(3):331-7.