Musnad Ahmad 1153:1148

Muhammad ibn Ja'far narrated to us, Sa'id narrated to us, from Qatadah, from Zurarah ibn Awfa, from Sa'd ibn Hisham, from 'Aishah: "That the Messenger of Allah (peace and blessings of Allah be upon him) ordered that the bells be cut from the necks of the camels on the day of Badr."