KHUDHUR, F. A.; REDHA, Z. A. A. Comparative Emissions of Syngas, Biogas, and LPG in Spark-Ignition Engines for Sustainable Power Generation. Engineering, Technology & Applied Science Research, Greece, v. 15, n. 6, p. 28635–28639, 2025. DOI: 10.48084/etasr.13864. Disponível em: https://etasr.com/index.php/ETASR/article/view/13864. Acesso em: 29 apr. 2026.