YAACOB, Nazeeruddin; PHANG, Chang. New Nonlinear Four-Step Method for $y’’=f(t,y)$. MATEMATIKA, [S. l.], v. 19, p. 47–56, 2003. DOI: 10.11113/matematika.v19.n.501. Disponível em: https://matematika.utm.my/index.php/matematika/article/view/501. Acesso em: 3 may. 2024.