^Settipani, Christian (1993). La préhistoire des Capétiens (481-987) - Première partie : Mérovingiens, Carolingiens et Robertiens
Sources
Le Jan, Regine (2000). "Continuity and Change in the Tenth Century Nobility". In Duggan, Anne (ed.). Nobles and Nobility in Medieval Europe: Concepts, Origins, Transformations. The Boydell Press.