Musannaf Ibn Abi Shayba 16:946

Abu Bakr narrated to us, he said: Affan narrated to us, he said: Hammad bin Salamah narrated to us, he said: Ubaydullah bin Abi Rafi’, the freed slave of the Messenger of Allah (may Allah bless him and grant him peace), informed me that Abdullah bin Ja’far used to wear his ring on his right hand.