Musannaf Ibn Abi Shayba 1:1638

1638. Abda narrated to us, from Hisham ibn Urwah, from Amr ibn Khuzaymah, from Umarah ibn Khuzaymah, from Khuzaymah ibn Thabit, who said: The Messenger of Allah (may Allah bless him and grant him peace) said regarding cleaning oneself (istinja) with three stones: "There is no dung (raji') in them."