CHRISTISON, David. Notices of an Ancient Fort and a Stone Circle at Wester Torrie, near Callander, Perthshire. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 36, p. 614–620, 1902. DOI: 10.9750/PSAS.036.614.620. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/6844. Acesso em: 18 jul. 2024.