Кадирбаева, Ж. М. “ On an Approximate Method for Nding of Solution of Nonlocal Boundary Value Problem for Systems of Loaded Hyperbolic Equations”. Journal of Mathematics, Mechanics and Computer Science, vol. 82, no. 3, Sept. 2014, pp. 26-35, https://bm.kaznu.kz/index.php/kaznu/article/view/67.