Cross, Arthur Lyon: . Macmillan, 1917. Hollister, C. Warren: . Yale University Press, 2001. (Yale Monarchs series) ISBN 0300098294 Matthew, Donald: . Oxford 2005. ISBN 0-340-74060-4 Thompson, Kathleen: «Affairs of State: the Illegitimate Children of Henry I». 29 (2003): 129-151.