Musannaf Ibn Abi Shayba 37:593

Waki’ narrated to us, he said: Al-A’mash narrated to us, from Abu Ishaq, from Ubayd ibn ‘Amr al-Khariqi, who said: I was one of the group who arrived and stayed at Dhu al-Marwa. They sent us to a group of the companions of Muhammad, may Allah bless him and grant him peace, and his wives, to ask them whether we should proceed or return. It was said to us: "Make Ali the last one you ask." He said: So we asked them, and all of them commanded us to proceed. Then we came to Ali and asked him. He said: "Did you ask anyone before me?" We said: "Yes." He said: "What did they command you to do?" We said: "They commanded us to proceed." He said: "But I do not command you to do so. Let the egg hatch."