References for Waltheof Earl, Earl, Earl of Huntingdon * of Northampton * of Northumberland
E. Brandenburg: Die Nachkommen Karls des Grossen. Leipzig 1936, Frankfurt 1964
Sir B.Burke: The Dormant and Extinct Peerage. London, 1866
F.M.Powicke, E.B.Fryde: Handbook of British Chronology. London, 1961
D.Schwennicke: Europäische Stammtafeln, Vol. III/4, Tafel 621. Marburg, 1989