Musannaf Ibn Abi Shayba 13:1622

Abu Bakr narrated to us, he said: Sufyan ibn ‘Uyaynah narrated to us, from ‘Abdullah ibn Abi Yazid, from Ibn ‘Abbas, that he disliked the sale of "ten for twelve," and he said: "It is the sale of the non-Arabs (al-A‘ajim)."