LOWE, Christopher. George Petrie and the ’brochs’ of Papa Westray. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 124, p. 173–187, 1995. DOI: 10.9750/PSAS.124.173.187. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/9495. Acesso em: 29 apr. 2024.