CZERNI, M. Another description of continuous solutions of a nonlinear functional inequality. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 7, p. 51–59, 2008. Disponível em: https://studmath.uken.krakow.pl/article/view/13269. Acesso em: 30 oct. 2026.