KARIMOV, K. S.; ABID, M. Biogas Digester with Simple Solar Heater. IIUM Engineering Journal, [S. l.], v. 13, n. 2, 2012. DOI: 10.31436/iiumej.v13i2.123. Disponível em: https://journals.iium.edu.my/ejournal/index.php/iiumej/article/view/123. Acesso em: 5 dec. 2021.