Selection of references used:
- 1: Paul de Rapin-Thoyras, The History of England, Volume 5
- 2: M H Keen, England in the Later Middle Ages, ISBN:0-415-02783-7, Erdington Library
- 3: Magnus Magnusson, Vikings!
- 4: R. W. Chambers, M.A., D.Lit., England Before the Norman Conquest, 1926, Longmans , Green and Co. Ltd (1926)
- 5: R. L. Storey, The Medieval World 800 - 1490, ISBN:0-09-178264-3
- 6: Byran Bevan, Henry VII: The First Tudor King, The Rubican Press
- 7: Neville Williams, Henry VII