NGUYEN, H. H. Hyers--Ulam stability, well-posedness, and data dependence for Fisher-type contractive mappings. Hong Duc University Journal of Science, [S. l.], n. 7, [s.d.]. Disponível em: https://hdujs.edu.vn/index.php/js/article/view/1127. Acesso em: 3 sep. 2026.