Musannaf Ibn Abi Shaybah

Hazrat Zuhri says that Umar bin Abdul Aziz called me and asked me about Qasamah. And he said that I am thinking of rejecting it. A villager comes and gives testimony, and an absent person gives testimony. I said, O Commander of the Faithful! You cannot reject it; the Holy Prophet (peace and blessings be upon him) made decisions through Qasamah, and after him, the Caliphs (also) made decisions through it.