Jervise, A. (1858) “Notices descriptive of the localities of certain Sculptured Stone Monuments in Forfarshire, &c., - Meigle, Essie, Glamis, Thornton, and Cossins. Part II”, Proceedings of the Society of Antiquaries of Scotland, 2, pp. 242–251. doi: 10.9750/PSAS.002.242.251.