RIYANTO, O.; ABDULLAH, M. H.; SETYONO, G. 2⁴ Factorial Design Optimization of Process Variables for Biodiesel Production from Waste Cooking Oil. Engineering, Technology & Applied Science Research, Greece, v. 16, n. 2, p. 33228–33232, 2026. DOI: 10.48084/etasr.15231. Disponível em: https://www.etasr.com/index.php/ETASR/article/view/15231. Acesso em: 2 may. 2026.