IMANGALIYEV, Y. ABOUT DIFFERENCE OF SOLUTION SINGULAR DISTURBED AND UNDISTURBED BOUNDARY PROBLEMS. Recent Contributions to Physics, [S. l.], v. 2018, n. 3, p. 122–125, 2018. Disponível em: https://bph.kaznu.kz/index.php/zhuzhu/article/view/1028. Acesso em: 9 feb. 2026.