1. H. Katalambula and R. Gupta, Energy Fuels, 23, 3392 (2009).
2. C.Z. Li, Advances in the science of victorian brown coals, Elsevier, Oxford (2004).
3. S. Sugita, T. Deguchi and T. Shigehisa, Kobe Steel Engineering Reports Vol. 53, Kobe Steel, Ltd., Japan (2003).
4. D. F. Umar, B. Daulay, H. Usui, T. Deguchi and S. Sugita, Coal Prep., 25, 31 (2005).
5. S. Kinoshita, S. Yomamoto, T. Deguchi and T. Shigehisa, Kobelco Technology Review No. 29, Kobe Steel, Ltd., Japan (2010).