References for Maud of Lancaster
Sir B.Burke:
The Dormant and Extinct Peerage.
London, 1866
J. Dupont, J. Saillot:
Cahiers de Saint-Louis.
Nantes, Angers, 1976 etc.
D.Schwennicke:
Europäische Stammtafeln, Vol. II, Tafel 83.
Marburg, 1984