A. FELIX; S. CHRISTOPHER; A. VICTOR DEVADOSS. A Nonagonal Fuzzy Number and Its Arithmetic Operation. International Journal of Mathematics And its Applications, [S. l.], v. 3, n. 2, p. 185–195, 2015. Disponível em: http://ijmaa.in/index.php/ijmaa/article/view/437. Acesso em: 8 may. 2024.