George Hay. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 117, p. 4–6, 1988. DOI: 10.9750/PSAS.117.4.6. Disponível em: https://soas-test.journals.ed.ac.uk/index.php/psas/article/view/10383. Acesso em: 26 oct. 2025.