Cleal, Christopher. “Large–leaved Annularia Species (Equisetopsida) in Pennsylvanian Variscan Euramerica–a Preliminary Review”. Journal of Palaeosciences 72, no. 2 (December 22, 2023): 153–174. Accessed May 16, 2024. https://www.jpsonline.co.in/index.php/jop/article/view/1859.