Musnad Ahmad 1156:242

'Abd al-Rahman narrated to us, from Malik, from Abu al-Aswad, from 'Urwah, from Zaynab bint Umm Salamah, from Umm Salamah: That she arrived while she was ill, so she mentioned that to the Prophet, peace and blessings of Allah be upon him. He said: "Perform the circumambulation (Tawaf) from behind the people while you are riding." She said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, while he was at the Ka'bah, reciting [Surah] al-Tur. 'Abdullah said: My father said: And I read it to 'Abd al-Rahman: She said: So I performed the circumambulation, and the Messenger of Allah, peace and blessings of Allah be upon him, was at that time praying beside the House, and he was reciting: "By the Mount (al-Tur) and a Book inscribed."