Aisagaliev S. А., and S. S. Aisagalieva. “Improper Integrals for Stability Theory of Multidimensional Phase Systems”. Journal of Mathematics, Mechanics and Computer Science 97, no. 1 (August 27, 2018): 38–53. Accessed October 13, 2024. https://bm.kaznu.kz/index.php/kaznu/article/view/483.