Musannaf Ibn Abi Shayba 27:285

Abu Mu'awiyah and Waki' narrated to us, from al-A'mash, from 'Abdullah ibn Murrah, from Abu al-Ahwas, from 'Abdullah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "I disassociate myself from every intimate friend (khalil) because of his intimate friendship (khullah), except that Allah has taken your companion as an intimate friend. And if I were to take an intimate friend, I would have taken Abu Bakr as an intimate friend." Except that Waki' said: "from his intimate friendship (khullihi)."