Simpson, J Y. β€œOn the Cat-Stane, Kirkliston: Is It Not the Tombstone of the Grandfather of Hengist and Horsa?”. Proceedings of the Society of Antiquaries of Scotland 4 (November 30, 1862): 119–169. Accessed November 24, 2024. https://journals.socantscot.org/index.php/psas/article/view/4606.