Mohammed , M.J. “ Lyapunov-Schmidt Method in Bifurcation Solutions of Nonlinear Fourth Order Differential Equation ”. University of Thi-Qar Journal of Science 3, no. 1 (May 13, 2019): 135-145. Accessed August 17, 2026. https://www.jsci.utq.edu.iq/index.php/main/article/view/218.