Musnad Ahmad 27:1925

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from al-Zuhri, from Salim, from Ibn 'Umar, who said: "I witnessed the Messenger of Allah, peace and blessings of Allah be upon him, when he ordered their stoning. When they were being stoned, I saw him shielding her with his hands, to protect her from the stones."