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^Runciman, Steven. A History of the Crusades: The Kingdom of Acre and the Later Crusades (Volume 3). Cambridge: Cambridge University Press. 1954: 111. ISBN 978-0-521-34772-3.
^Evergates, Theodore (2007). The Aristocracy in the County of Champagne, 1100-1300. University of Pennsylvania Press. ISBN 0812201884.