Musnad Ahmad 570:2

'Ali ibn Bahr narrated to us, al-Walid ibn Muslim narrated to us, Sa'id ibn 'Abd al-'Aziz narrated to us, from Rabi'ah ibn Yazid, from 'Abd al-Rahman ibn Abi 'Amirah al-Azdi, from the Prophet, may Allah bless him and grant him peace, that he mentioned Mu'awiyah and said: "O Allah, make him a guide, rightly guided, and guide [others] through him."