Zodrow, Erwin L. “Note on Different Kinds of Attachments in Trigonocarpalean (Medullosales) Ovules from the Pennsylvanian Sydney Coalfield, Canada”. Atlantic Geoscience 40, no. 2/3 (October 10, 2004). Accessed April 23, 2024. https://journals.lib.unb.ca/index.php/ag/article/view/1039.