Tokibetov Ж. .; Bashar . Н. .; Pirmanova А. . THE CAUCHY-DIRICHLET PROBLEM FOR A SYSTEM OF FIRST-ORDER EQUATIONS. Bulletin of Abai KazNPU. Series of Physical and Mathematical sciences, Almaty, Kazakhstan, v. 72, n. 4, p. 68–72, 2020. DOI: 10.51889/2020-4.1728-7901.10. Disponível em: https://bulletin-phmath.kaznpu.kz/index.php/ped/article/view/80. Acesso em: 14 dec. 2025.