Hulme, Peter D, and Jennifer Shirriffs. “Pollen Analysis of a Radiocarbon-Dated Core from North Mains, Strathallan, Perthshire”. Proceedings of the Society of Antiquaries of Scotland 115 (November 30, 1987): 105–113. Accessed April 19, 2024. https://journals.socantscot.org/index.php/psas/article/view/9204.