Koonaphapdeelert, Sirichai, and Orranat Huangsakuncharoen. 2018. “Effect of Water Recirculation Rate on Biogas Upgrading by Algae in Air-Lift Photobioreactor”. Journal of Renewable Energy and Smart Grid Technology 13 (1). https://ph01.tci-thaijo.org/index.php/RAST/article/view/65161.