Musannaf Ibn Abi Shayba 27:492

Waki’ narrated to us, from Shu’bah, from al-Hurr ibn Sayyah, from ‘Abd al-Rahman ibn al-Akhnas, from Sa’id ibn Zayd, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "Ali is in Paradise."