Meyer, Kuno (1896), «Early relations Between Gael and Brython», en Evans, E. Vincent, ed., Transactions of the Honourable Society of Cymmrodorion, Session 1895–1896 I, London: Honourable Society of Cymmrodorion, pp. 55-86.
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Birley, Anthony Richard The Roman Government of Britain OUP Oxford (29 Sep 2005) ISBN 978-0199252374 pp.461-463 [1]