Musannaf Ibn Abi Shayba 19:463

Abu Bakr narrated to us, he said: Ibn Mushir narrated to us, from al-Shaybani, from Ikrimah, who said: A woman came to Ali and said: "My husband has had intercourse with my slave girl." He said: "If you are truthful, we will stone him, and if you are lying, we will flog you." Then she waited for the people until they became intermingled, and the woman went away.