Robertson, Thomas. “Letter from Thomas Robertson, Esq., to the Earl of Buchan, Respecting the Discovery of a Stone Coffin at Arbroath, Supposed to Contain the Remains of King William the Lyon”. Archaeologia Scotica 3 (November 30, 1832): 297–298. Accessed December 4, 2024. https://journals.socantscot.org/index.php/arch-scot/article/view/240.