Musnad Ahmad 25:164

Yahya narrated to us, from Hisham ibn Urwah, Wahb ibn Kaysan narrated to me, from Muhammad ibn Amr ibn Ata, from Ibn Abbas, he said: And Muhammad ibn Ali ibn Abdullah ibn Abbas narrated to me, from his father, from Ibn Abbas, he said: And al-Zuhri narrated to me, from Ali ibn Abdullah, from Ibn Abbas: "That the Messenger of Allah (peace and blessings of Allah be upon him) ate meat—or a piece of meat—then prayed and did not touch water."