Parasidis, I.N., and E. Providas. “Factorization Method for Solving Systems of Second-Order Linear Ordinary Differential Equations”. Eurasian Mathematical Journal 16, no. 2 (June 30, 2025): 55–73. Accessed January 4, 2026. https://emj.enu.kz/index.php/main/article/view/759.