AldashevS. A. “Some Problems for Multidimensional Integro-Differential Equations of Hyperbolic Type”. Ukrains’kyi Matematychnyi Zhurnal 52, no. 5 (May 25, 2000): 590-595. Accessed November 28, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4453.