VALDIVIA ALCALÁ, Ramón. Economic valuation in a sand mine. REVISTA TERRA LATINOAMERICANA, [S. l.], v. 28, n. 3, p. 255–263, 2010. Disponível em: https://www.terralatinoamericana.org.mx/index.php/terra/article/view/1232. Acesso em: 1 may. 2025.