Radhakrishna, B. P. “Annual Report 1988-89 of Birbal Sahni Institute of Palaeo-Botany, Lucknow, India”. Journal of Geological Society of India, vol. 35, no. 2, Feb. 1990, pp. 222-, https://geosocindia.com/index.php/jgsi/article/view/66693.