IMANBAYEVA, A. Содержание 1 (60) 2017. Recent Contributions to Physics, [S. l.], v. 60, n. 1, p. 159–162, 2017. Disponível em: https://bph.kaznu.kz/index.php/zhuzhu/article/view/893. Acesso em: 5 дек. 2025.