1985. ISBN 0-907521-13-4. Hanson, WilliamS. The Roman Presence: Brief Interludes. Edwards, Kevin J.; Ralston, Ian B. M. (编). Scotland After the Ice Age:
PMID 27397586. S2CID 42525698. doi:10.1111/apt.13706. (原始内容存档于2021-12-22) (英语). Lacy, Brian E.; Pimentel, Mark; Brenner, Darren M.; Chey, William D.; Keefer