Ulam-Hyers Stability of Trigonometric Functional Equation with Involution. Communications in Mathematical Research, [S. l.], v. 34, n. 2, p. 141–148, 2019. DOI: 10.13447/j.1674-5647.2018.02.06. Disponível em: https://global-sci.com/index.php/cmr/article/view/8959. Acesso em: 5 dec. 2025.