WOOLLISCROFT, David J; HOFFMANN, Birgitta. The Roman Gask system tower at Shielhill South, Perthshire: excavations in 1973 and 1996. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 128, p. 441–460, 1999. DOI: 10.9750/PSAS.128.441.460. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/10014. Acesso em: 25 apr. 2024.