Musnad Ahmad 30:3213

Muhammad ibn Ja'far and Rawh said: Shu'bah, or Sa'id, narrated to us, from Qatadah, from Abu Rafi', from Abu Hurairah, from the Prophet, peace and blessings of Allah be upon him, who said: "Indeed, there is an hour in Friday; no Muslim servant coincides with it while praying, asking Allah for something good, but He will give it to him."