Mackay, Angus. 1906. “Notes on a Slab With Incised Crescentic Design, Stone Mould for Casting Spear-Heads, a Cup-Marked Stone, Holy-Water Stoup, and Other Antiquities in Strathnaver, Sutherlandshire”. Proceedings of the Society of Antiquaries of Scotland 40 (November):128-33. https://doi.org/10.9750/PSAS.040.128.133.