RITCHIE, James. Cup-Marks on the Stone Circles and Standing-Stones of Aberdeenshire and part of Banffshire. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 52, p. 86–121, 1918. DOI: 10.9750/PSAS.052.86.121. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/7444. Acesso em: 24 apr. 2024.