[1]
Petrie, G. 1867. Notice of Ruins of Ancient Dwellings at Skara, Bay of Skaill, in the Parish of Sandwich, Orkney, recently excavated. Proceedings of the Society of Antiquaries of Scotland. 7, (Nov. 1867), 201–219. DOI:https://doi.org/10.9750/PSAS.007.201.219.