Mangerud, Gunn, Gilda Lopes, and Jonathan Bujak. “Carboniferous Palynoevents in the Circum-Arctic Region”. Atlantic Geoscience 57, no. 1 (January 24, 2021): 041–055. Accessed May 20, 2022. https://journals.lib.unb.ca/index.php/ag/article/view/31496.