Musnad Ahmad 31:462

'Abd al-Malik ibn 'Amr narrated to us, Hisham and Yazid narrated to us, Hisham informed us, from Yahya ibn Abi Kathir, from Abu Salamah, from Abu Sa'id al-Khudri, who said: "We used to be provided with mixed dates during the time of the Messenger of Allah, may Allah bless him and grant him peace."