Fritz, W. H., J. D. Aitken, I. A. McIlreath, and R. Ludvigsen. “‘The Burgess Shale:’ Not in the Shadow of the Cathedral Escarpment”. Geoscience Canada 17, no. 2 (June 6, 1990). Accessed April 20, 2024. https://journals.lib.unb.ca/index.php/GC/article/view/3661.