Birley, Eric, Ian A Richmond, J A Stanfield, and W Percy Hedley. “Excavations at Birrens, 1936-37”. Proceedings of the Society of Antiquaries of Scotland 72 (November 30, 1938): 275–347. Accessed May 3, 2024. https://journals.socantscot.org/index.php/psas/article/view/8073.