1. J. Richard, Les ducs de Bourgogne et In formntion du duché du Xle nu XlVe siècles (Société des Belles Lettres: Paris, 1954).
2. Heather J. Tanner, “Reassessing King Stephen’s Continental Strategies,” Medievnlin et Humnnisticn: Studies in Medievnl nnd Rennissnnce Culture, 26 (1999): 101–117.
3. John Gillingham, The Angevin Empire (Oxford University Press: New York, 2001), second ed., p. 64.
4. Kathleen Thompson, Rower nnd Border Lordships: The Count of the Perche (1000–1226) (Boydell: Rochester, NY, 2002).
5. Robert Hajdu, “Castles, Castellans and the Structure of Politics in Poitou, 1152–1271,” Journnl of Medievnl History 44 (1978): 27–54.