Southesk, Earl of. “The Oghams on the Brodie and Aquhollie Stones, With Notes on the Inscriptions of the Golspie and Newton Stones, and a List of the Oghams in Scotland”. Proceedings of the Society of Antiquaries of Scotland, vol. 20, Nov. 1886, pp. 14-40, doi:10.9750/PSAS.020.14.40.