ANDERSON, J. Notice of the Excavation of the Brochs of Yarhouse, Brounaben, Old Stirkoke, Bowermadden, and Dunbeath, in Caithness; with Remarks on the Period of the Brochs; and an Appendix, containing a List of Brochs in Scotland, and Early Notices of many of them. Proceedings of the Society of Antiquaries of Scotland, v. 9, p. 292, 30 nov. 1872.