Adam Clarke on Genesis 36:16

Duke Korah - This Dr. Kennicott pronounces to be an interpolation. "It is certain, from Gen 36:4, that Eliphaz was Esau's son by Adah; and from Gen 36:11, Gen 36:12, that Eliphaz had but six sons, Teman, Omar, Zepho, Gatam, Kenaz, and Amalek. It is also certain, from Gen 36:5, Gen 36:14, that Korah was the son of Esau (not of Eliphaz) by Aholibamah; and as such he is properly mentioned in Gen 36:18 : These are the sons of Aholibamah, Esau's wife: duke Jeush, duke Jaalam, Duke Korah. It is clear, therefore, that some transcriber has improperly inserted duke Korah in Gen 36:16; from which interpolation both the Samaritan text and the Samaritan version are free." - Kennicott's Remarks. Everything considered, I incline to the opinion that these words were not originally in the text.