On the Occasion of the Seventieth Birthday of Professor Chang Kung-Ching. Journal of Partial Differential Equations, [S. l.], v. 19, n. 3, p. 193–199, 2006. Disponível em: https://www.global-sci.com/index.php/jpde/article/view/4071. Acesso em: 5 dec. 2025.