CHRISTISON, David. The Prehistoric Fortresses of Treceiri, Carnarvon; and Eildon, Roxburgh. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 28, p. 100–119, 1894. DOI: 10.9750/PSAS.028.100.119. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/6546. Acesso em: 2 may. 2024.