COLES, Frederick R. Notices of Rock-Hewn Caves in the Valley of the Esk and other Parts of Scotland. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 45, p. 265–301, 1911. DOI: 10.9750/PSAS.045.265.301. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/7218. Acesso em: 6 may. 2024.