Kalybay, A. A., and D. S. Karatayeva. “Strong Non-Oscillation and Oscillation Second Order Half-Linear Difference Equation”. Journal of Mathematics, Mechanics and Computer Science 104, no. 4 (December 19, 2019): 32–43. Accessed July 3, 2024. https://bm.kaznu.kz/index.php/kaznu/article/view/674.