Mihali, Klevis, et al. “Thinking Outside the Box: Case Report of a Rare Quadricuspid Aortic Valve As an Underrecognized Cause of Heart Failure and Atrial Fibrillation”. Journal of Medical Cases, vol. 16, no. 8, Aug. 2025, pp. 277-81, https://doi.org/10.14740/jmc5153.