BARCLAY, Gordon J; MORRIS, Ron. The anti-invasion defences of the Forth and Tay estuaries, eastern Scotland: 1900 to 1919. Proceedings of the Society of Antiquaries of Scotland, [S. l.], v. 148, p. 283–331, 2019. DOI: 10.9750/PSAS.148.1264. Disponível em: https://journals.socantscot.org/index.php/psas/article/view/10266. Acesso em: 1 may. 2024.