Sharma, B.D. “Studies on the Transfusion Cells in Petrified Leaves of Ptilophyllum and Nipaniophyllum from the Rajmahal Hills, India”. Journal of Palaeosciences 30 (December 31, 1982): 181–184. Accessed November 24, 2024. https://jpsonline.co.in/index.php/jop/article/view/1449.