1. BPPT, Indonesia Energy Outlook 2019: The Impact of Increased Utilization of New and Renewable Energy on the National Economy (PPIPE BPPT, Jakarta, 2019).
2. BPPT, Indonesia Energy Outlook 2020-Special Edition Dampak Pandemi COVID-19 Terhadap Sektor Energi di Indonesia (PPIPE BPPT, Jakarta, 2020).
3. Clean liquid fuels from direct coal liquefaction: chemistry, catalysis, technological status and challenges
4. S. Choudhary, A. Thakur, A. Gupta and P.S.B. Ambekar, Int. Res. J. Eng. Technol. 3, 2704–2708 (2016).
5. Clean Coal Technologies in China: Current Status and Future Perspectives