SOMERVILLE, Andrew R. The ancient sundials of Scotland. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 117, p. 233–264, 1988. DOI: 10.9750/PSAS.117.233.264. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/9308. Acesso em: 2 may. 2024.