In his Íslenzkir þjóður og ævintýri, published in 1862-1864, Jón Árnason identifies the tale's source as a manuscript written by Sveinbjörn Guðmundsson.
[1] An earlier poetic telling of the tale, titled Rímur af Hermóði, was written in the late 18th century by Eiríkur Laxdal.
In a dream, a woman told her that she was leaving her a rope to climb the cliffs, a thread to follow to find Hermod, and a belt to keep her from going faint with hunger.
Hadvor told her father the whole story, and the evil Queen and her daughter were turned into a rat and a mouse and killed by Hermod.
The tale is classified according to the international Aarne-Thompson-Uther Index as type ATU 444, "Enchanted Prince Disenchanted.