Ысмагул R.S., and Б.О. Жумартова. “CHARACTERISTIC FUNCTION OF THE SYSTEM D–EQUATIO”. Bulletin of Abai KazNPU. Series of Physical and mathematical sciences 75, no. 3 (September 30, 2021): 29–34. Accessed November 22, 2024. https://bulletin-phmath.kaznpu.kz/index.php/ped/article/view/334.