Edwards, A. J. H. and Bryce, T. H. (1927) “Excavation of Graves at Ackergill and of an Earth-house at Freswick Links, Caithness, and a Description of the Discovery of a Viking Grave at Reay, Caithness: With a Preliminary Note on the Skeletal Remains from the Various Graves”, Proceedings of the Society of Antiquaries of Scotland, 61, pp. 196–209. doi: 10.9750/PSAS.061.196.209.