Musnad Abu Ya'la al-Mawsili 153:187

Nasr ibn Ali narrated to us, Abdullah ibn Dawud informed us, from Hisham ibn Sa’d, from Umar ibn Asid, from Ibn Umar, who said: We used to say during the time of the Messenger of Allah (peace and blessings of Allah be upon him): The Prophet, then Abu Bakr, then Umar. And Ali ibn Abi Talib was given three qualities; for one of them to be mine is more beloved to me than red camels: He married Fatimah and she bore him children, the doors were closed except for his door, and the banner was given to him on the day of Khaybar.