BARCLAY, Gordon J; BROOKS, M; RIDEOUT, James S. The cup and ring marked stone at Newbigging Farm, Perth & Kinross District, Tayside Region. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 112, p. 559–561, 1983. DOI: 10.9750/PSAS.112.559.561. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/9103. Acesso em: 20 apr. 2024.