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Bingley, William (1839), Excursions in North Wales: including Aberystwith and the Devil's Bridge, intended as a guide to tourists (3 ed.), Longman, Orme, p. 226
Carlton, Charles (1992), Going to the Wars: The Experience of the British Civil Wars, 1638-1651 (illustrated, reprint ed.), Routledge, p. 258, ISBN 9780415103916
Pettifer, Adrian (2000), Welsh Castles: A Guide by Countries (illustrated ed.), Boydell & Brewer, p. 66, ISBN 9780851157788
Williams, W.R. (1895), Parliamentary History of the Principality of Wales,from the earliesr times to the present day, 1541-1895 ..., Brecknock: Priv. Print. for the author by E. Davis and Bell, p. 116