“Notices descriptive of the localities of certain Sculptured Stone Monuments in Forfarshire, viz., - Benvie, and Invergowrie; Strathmartin, and Balutheran; Monifieth; Cross of Camus, and Arbirlot. Part III” (1859) Proceedings of the Society of Antiquaries of Scotland, 2, pp. 442–452. doi:10.9750/PSAS.002.442.452.