References for Elizabeth de Courtenay
Sir B.Burke:
The Dormant and Extinct Peerage.
London, 1866
D.Schwennicke:
Europäische Stammtafeln, Vol. III/4, Tafel 630.
Marburg, 1989
F.L.Weis:
Ancestral Roots of Sixty Colonists.
6th Ed., Baltimore, 1988