Singh, J., S. Mahanti, and K. Singh. “Geology and Evaluation of Hydrocarbon Prospects of Tethyan Sediments in Spiti Valley, Spiti and Zanskar, Himanchal Pradesh”. Himalayan Journal of Sciences, vol. 2, no. 4, Feb. 2008, p. 250, doi:10.3126/hjs.v2i4.931.