Selection of references used:

  • 1: James Forde-Johnston, Great Medieval Castles of Britain, 1979
  • 2: John H Harvey, Henry Yevele, LIfe of an English Architect
  • 3: John Guy, Castles in Sussex, 1984, ISBN:ISBN-0-85033-523-X, Philimore & Co, Ltd - The Camelot Press Ltd (1984)