Laing, Henry. “A Note Respecting the Sculptured Cross at St Vigeans, Near Arbroath; Of Which Casts by Mr Henry Laing, Seal Engraver, Were Exhibited”. Proceedings of the Society of Antiquaries of Scotland, vol. 1, Nov. 1855, pp. 294-6, doi:10.9750/PSAS.001.294.296.