Musnad Ahmad 941:28

Abu al-Yaman narrated to us, Shu'ayb informed us, from al-Zuhri, 'Urwah ibn al-Zubayr informed me, that Usamah ibn Zayd informed him: That the Prophet, peace and blessings of Allah be upon him, rode a donkey upon a saddle-pad over which was a Fadakiyyah velvet cloth. He had Usamah ibn Zayd ride behind him to visit Sa'd ibn 'Ubadah among the Banu al-Khazraj before the Battle of Badr. He mentioned it and said: "The al-Bahrah."