Mazidi Mohsen, Karimi Ehsan, Rezaie Peyman, and Vatanparast Hassan. “The Impact of Vitamin D Supplement Intake on Vascular Endothelial Function; A Systematic Review and Meta-Analysis of Randomized Controlled Trials”. Food & Nutrition Research 610 (March 20, 2017). Accessed June 25, 2022. https://foodandnutritionresearch.net/index.php/fnr/article/view/1145.