Kocherla, Cyrus, and Kalgi Modi. “Congenital Quadricuspid Aortic Valve, a Rare Cause of Aortic Insufficiency in Adults: Case Report”. Journal of Cardiology and Cardiovascular Medicine, vol. 2, no. 1, Jan. 2017, pp. 003-7, doi:10.29328/journal.jccm.1001005.