Geddes, George. “The Royal Commission on the Ancient and Historical Monuments of Scotland, Angus Graham and Gordon Childe (1935–46)”. Proceedings of the Society of Antiquaries of Scotland 146 (November 30, 2017): 275-309. Accessed February 3, 2023. http://journals.socantscot.org/index.php/psas/article/view/9853.