Joass, J. M. Notice of the Excavation of the Pictish Towers at Cinntrolla, Carnliath, and Craig-Carril in Sutherland, With Notes on Neighbouring Brochs; And an Appended Report by T. Aitken, M.D., F.A.S.L., Inverness, on the Crania Found in and about Them. PSAS 1872, 9, 60.