Historia Britonum 
"In the meantime, three vessels, exiled from Germany, arrived in Britain. They were commanded by Horsa and Hengist, brothers, and sons of Wihtgils. Wihtgils was the son of Witta; Witta of Wecta; Wecta of Woden; Woden of Frithowald; Frithowald of Frithuwulf; Frithuwulf of Finn; Finn of Godwulf; Godwulf of Geat, who, as they say, was the son of a god, not of the omnipotent God and our Lord Jesus Christ (who before the beginning of the world, was with the Father and the Holy Spirit, co-eternal and of the same substance, and who, in compassion to human nature, disdained not to assume the form of a servant), but the offspring of one of their idols, and whom, blinded by some demon, they worshipped according to the custom of the heathen."
There is some question regarding the ancestor of Godwulf, listed as "Geat" in Historia Brittonum. Regarding these questions, English scholar Hector Munro Chadwick comments:
"The genealogies do not end with Woden but go back to a point five generations earlier, the full list of names in the earlier genealogies being Frealaf—Frithuwulf—Finn—Godwulf—Geat. Of the first four of these persons nothing is known. Asser says that Geat was worshipped as a god by the heathen, but this statement is possibly due to a passage in Sedulius' Carmen Paschale which he has misunderstood and incorporated in his text. It has been thought by many modern writers that the name is identical with Gapt which stands at the head of the Gothic genealogy in Jordanes, cap. 14; but the identification is attended with a good deal of difficulty."
Prose Edda 
In the Icelandic Prose Edda, a 13th century work by Snorri Sturluson, chapter 3 of the Prologue contains his Euhmerized account of Norse mythology. In this section, Snorri gives a genealogy stating that Guðúlfr is one of the descendants of Thor and Sif. The genealogy also states that Guðúlfr is an ancestor of Odin.
- Six Old English Chronicles ed. J. A. Giles. London: Henry G. Bohn (1848)
- Chadwick, Hector Munro. The Origin of the English Nation (1907) (Page 270)