Tahirkheli, R. A. K., S. Dongli, P. Yushang, D. Wanming, Z. Yuquan, S. Baqri, and H. Dawood. “Review of Stratigraphy of the Upper Hunza Valley (UHV), NW Karakoram, Pakistan”. Journal of Himalayan Earth Sciences, vol. 23, no. 1, Nov. 1990, pp. 203-14, http://ojs.uop.edu.pk/jhes/article/view/1383.