CHRISTISON, Robert. Notice of a Knocking-Stone or Barley Mortar of Granite, from Ballachulish, now presented to the Museum. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 16, p. 25–26, 1882. DOI: 10.9750/PSAS.016.25.26. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/5993. Acesso em: 27 apr. 2024.