Arisanti R, Yusuf M, Faizal M. Study of the Effect of Proximate, Ultimate, and Calorific Value Analysis on Methane Gas Emission (CH4) on Combustion of Coal for Sustainable Environment. sci. technol. indones. [Internet]. 2018 Apr. 16 [cited 2024 Dec. 8];3(2):100-6. Available from: https://sciencetechindonesia.com/index.php/jsti/article/view/88