Boudiaf, EH., M. abdelbaki, and MO AMRANE. “Valve Surgery After the Age Of 70: Evaluation Risk Factors for Hospital Mortality”. Clinical Medicine And Health Research Journal 4, no. 1 (February 21, 2024): 795–797. Accessed January 10, 2025. https://mail.cmhrj.com/index.php/cmhrj/article/view/316.