Musannaf Ibn Abi Shayba 18:1093

Abu Bakr narrated to us, he said: Yazid ibn Harun narrated to us, from Hammad ibn Salamah, from Hisham, from his father, regarding the *qasamah* (oath-taking in cases of homicide): He continued to act upon it during the Pre-Islamic period (Jahiliyyah) and in Islam.