Zhang Y, Xu R-, Li S, Zhu C-, Guo Y-, Sun J, Li J-. Association of plasma small dense LDL cholesterol with PCSK9 levels in patients with angiographically proven coronary artery disease. Nutrition, Metabolism and Cardiovascular Diseases. 2015 Apr;25(4):426–33. doi: 10.1016/j.numecd.2015.01.006.