Musannaf Ibn Abi Shayba 27:316

31954. Abd al-Rahim ibn Sulayman narrated to us, from Mis'ar, from Abu 'Awn al-Thaqafi, from Abu Salih al-Hanafi, from Ali ibn Abi Talib, who said: It was said to me and to Abu Bakr al-Siddiq on the day of Badr: "With one of you is Gabriel, and with the other is Michael." And Israfil is a mighty angel who witnesses the battle or stands in the ranks.