Musnad Ahmad 924:5

'Attab ibn Ziyad narrated to us, 'Abdullah informed us, Yunus informed us, from al-Zuhri, Abu Bakr ibn 'Abd al-Rahman narrated to me, Marwan ibn al-Hakam informed us, from 'Abd al-Rahman ibn al-Aswad ibn 'Abd Yaghuth, from Ubayy ibn Ka'b, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Indeed, some poetry is wisdom." 'Abdullah ibn al-Mubarak said: And Ma'mar narrated to me the same, except that he placed 'Urwah in the place of Abu Bakr.