R. K. SINGH, K. N, SINGH, S. K. DHANORIA, A. BHATT, and A. DIXTT, “ Petrochemistry and Depositional Environment of Permian Coals of Basundhara Block, Ib-Valley Coal field, Orissa, India”, IJEEG, vol. 1, no. 2, pp. 36–41, Jan. 2010.