Tirmidhi 1679

Hasan. Abu Dawud also reported it in the Book of Jihad, chapter on banners and flags, hadith 2592, as did Ibn Majah, hadith 2817, and Nasai, hadith 2869, from the narration of Yahya bin Adam through the same chain. Hakim graded it sahih according to the criteria of Muslim, 2/104, 105. It has corroborating narrations, see hadith 1681.