Raymund F. Wood, The three books of the Deeds of the Saxons, unpublished doctoral dissertation, University of California, Berkeley, 1949, available from ProQuest Dissertations & Theses
One or more of the preceding sentences incorporates text from a publication now in the public domain: Holland, Arthur William (1911). "Widukind". In Chisholm, Hugh (ed.). Encyclopædia Britannica. Vol. 28 (11th ed.). Cambridge University Press. pp. 620–621.