Note 249 — Chapter VIII · THE USE OF FICTION IN THE HEROIC POEMS.
Reading edition
It would be difficult to doubt its historical origin if it could be proved that the hero's father was originally identical with Sigemund the son of Waelse (Völsungr), who figures in Beowulf; for the two stories are almost entirely independent of each other and refer to quite different regions. The adventure with the dragon, which is related both of Sigurðr and Sigemund, shows that they were connected in very early times. Still I know no real proof of original identity.