Musnad Ahmad 31:190

Yahya narrated to us, from Anis ibn Abi Yahya, who said: My father narrated to me, saying: I heard Abu Sa’id: Two men differed—or disputed—a man from Banu Khudrah and a man from Banu ‘Amr ibn ‘Awf, regarding the mosque which was founded upon piety. The Khudri said: "It is the Mosque of the Messenger of Allah, may Allah bless him and grant him peace." And the ‘Amri said: "It is the Mosque of Quba." So they came to the Messenger of Allah, may Allah bless him and grant him peace, and asked him about that. He said: "It is this mosque of mine, the Mosque of the Messenger of Allah, may Allah bless him and grant him peace." And he said: "And in that one is much good," meaning the Mosque of Quba.