FERRARO, P. J.; KISS, A. Direct payments to conserve biodiversity. Himalayan Journal of Sciences, [S. l.], v. 1, n. 2, p. 81–83, 2006. DOI: 10.3126/hjs.v1i2.200. Disponível em: https://nepjol.info/index.php/HJS/article/view/200. Acesso em: 1 sep. 2024.