Selection of references used:
- 1: R. L. Mackie & J. Ross, Kings and Queens of Scotland, 2008, ISBN:ISBN-978-1-902407-66-1, Geddes and Gosset (2008)
- 2: Arthur Hassell, A Handbook of European History 4761871
- 3: Susan Ross, The Castles of Scotland, ISBN:0-85097-184-5
- 4: M.T.Clanchy, England and its Rulers
- 5: Various, The Cistercian Abbeys of Britain, 1998, ISBN:0-7134-8392-X, B.T.Batsford Ltd (1998)
- 6: Derek Wilson, The Tower (1078 - 1978)
- 7: Powicke, The Thirteenth Century
- 8: John Kinross, Discovering Castles in England and Wales, Shire Publications Ltd
- 9: H.W.C.Davis, England under the Normans and Angevins, 1949
- 10: John Julius Norwich, A History of Venice
- 11: John Corbet Anderson, Shropshire: Its Early History and Antiquities
- 12: John J. Robinson, Born in Blood, ISBN:0-87131-602-1, M. Evans & Company / New York, Geoff Bath