Hedges, J., D. Harkness, R. Jones, C. Tasker, P. Murphy, R. Chaplin, S. Trewin, and S. Sofranoff. “Excavation of Two Orcadian Burnt Mounds at Liddle and Beaquoy”. Proceedings of the Society of Antiquaries of Scotland, Vol. 106, Nov. 1977, pp. 39-98, doi:10.9750/PSAS.106.39.98.