Musnad Ahmad 30:510

'Abd al-Razzaq narrated to us, Ma'mar narrated to us, from al-Zuhri, from Abu Salamah ibn 'Abd al-Rahman and 'Ubayd Allah ibn 'Abd Allah ibn 'Utbah, that they both heard Abu Hurayrah saying: The Messenger of Allah (may Allah bless him and grant him peace) said: "Shall I not inform you of the best of the houses of the Ansar?" They said: "Yes, O Messenger of Allah." He said: "Banu 'Abd al-Ashhal," and they are the clan of Sa'd ibn Mu'adh. They said: "Then who, O Messenger of Allah?" He said: "Then Banu al-Najjar." They said: "Then who, O Messenger of Allah?" He said: "Then Banu al-Harith ibn al-Khazraj." They said: "Then who, O Messenger of Allah?" He said: "Then Banu Sa'idah." They said: "Then who, O Messenger of Allah?" He said: "Then in every house of the Ansar there is good."