Charles Ellicott Commentary Genesis 36:20

"These are the sons of Seir the Horite, the inhabitants of the land: Lotan and Shobal and Zibeon and Anah," — Genesis 36:20 (ASV)

The sons of Seir the Horite. —This genealogy is given partly because it contains that of Aholibamah, but chiefly because the Horites were eventually fused with the descendants of Esau, and together formed the Edomites.