ELLIOT, J Walter; HENIG, Martin. Engraved gemstones from the Roman frontier post at Newstead, Roxburghshire. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 112, p. 295–299, 1983. DOI: 10.9750/PSAS.112.295.299. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/9086. Acesso em: 27 apr. 2024.