R. K. SINGH, K. N. SINGH, S. K. DHANORIA, A. BHATT, and A. DIXIT. “Petrochemistry and Depositional Environment of Permian Coals of Basundhara Block, Ib-Valley Coalfied, Orissa,India”. International Journal of Economic and Environmental Geology, vol. 1, no. 1, Mar. 2010, pp. 36-41, doi:10.46660/ijeeg.v1i1.645.