On the correctness of non-local boundary value problems with an integral condition for fourth-order quasi-hyperbolic equations. Kazakh Mathematical Journal, [S. l.], v. 24, n. 2, p. 6–15, 2025. DOI: 10.70474/2024-2-01. Disponível em: https://mathjournal.kz/index.php/kmj/article/view/35. Acesso em: 25 feb. 2025.