Calder, Charles S T. “Notice of Two Standing Stones (one With Pictish Symbols) on the Lands of Peterhead Farm, Near Gleneagles, Perthshire”. Proceedings of the Society of Antiquaries of Scotland 81 (November 30, 1949): 1–7. Accessed November 22, 2024. https://journals.socantscot.org/index.php/psas/article/view/8270.