Obtaining biogas from manure and coffee pulp beef. Revista Universidad de Guayaquil, [S. l.], v. 121, n. 3, p. 47–54, 2015. DOI: 10.53591/rug.v121i3.386. Disponível em: https://revistas.ug.edu.ec/index.php/rug/article/view/272. Acesso em: 5 dec. 2025.