Musannaf Ibn Abi Shayba 3:4312

Abu Bakr narrated to us, he said: Abu Mu'awiyah narrated to us, from al-A'mash, from Ibrahim, from 'Alqama, from 'Umar, who said: The Messenger of Allah (peace and blessings of Allah be upon him) used to spend the night conversing with Abu Bakr regarding some matter of the Muslims, and I would be with him. And he spent the night with him one night, and I was with him.