MURRAY, Alexander. On the Sculpturings of Cups and Concentric Rings observed on Stones and Rocks in various parts of Scotland, &c. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 5, p. 299, 1865. DOI: 10.9750/PSAS.005.299.2. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/5137. Acesso em: 19 apr. 2024.