Musnad Ahmad 30:2914

Muhammad ibn Ja'far narrated to us, he said: Shu'bah narrated to us, he said: Sa'd ibn Ibrahim narrated to us, he said: I heard Abu Salamah, and he asked al-Agharr about this hadith, so al-Agharr narrated that he heard Abu Hurairah saying: Verily, the Messenger of Allah, peace and blessings of Allah be upon him, said: "A prayer in this mosque of mine is better than a thousand prayers in what is other than it of the mosques, except the Ka'bah."