WAHAB, Abd Fatah; MD TAP, Abu Osman. Padat-C Kabur. MATEMATIKA, [S. l.], v. 15, p. 129–134, 1999. DOI: 10.11113/matematika.v15.n.483. Disponível em: https://matematika.utm.my/index.php/matematika/article/view/483. Acesso em: 9 may. 2024.