Boichuk О. A.; MAKAROV, V. L.; FERUK, V. A. A criterion of solvability of resonant equations and construction of their solutions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 71, n. 10, p. 1321–1330, 2019. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1517. Acesso em: 5 dec. 2025.