Souvannasouk, Vannasinh, Oudtakhone Singthong, Phoukhanh Sayavongsa, Saneth Meas, Thanousinh Phaxaisithidet, and Salongxay Fongsamouth. “Revolutionizing biogas generation: Polyethylene tubular digesters for household pig farms”. Maejo International Journal of Energy and Environmental Communication 5, no. 1 (February 10, 2023): 6–13. accessed January 7, 2026. https://ph02.tci-thaijo.org/index.php/MIJEEC/article/view/250029.