Yong-dong, Wang. “Palynological Zonations and Paleoecology of Carboniferous Sequence from Zhongwei of Ningxia, Northwest China”. Journal of Palaeosciences 44 (December 31, 1995): 48–61. Accessed April 27, 2024. https://jpsonline.co.in/index.php/jop/article/view/1201.