CALLANDER, J Graham; GRANT, Walter G. Long stalled cairn at Blackhammer, Rousay, Orkney. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 71, p. 297–308, 1937. DOI: 10.9750/PSAS.071.297.308. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/8049. Acesso em: 3 may. 2024.