Musnad Ahmad 30:706

Ibrahim ibn Khalid narrated to us, Rabah narrated to us, Ma'mar narrated to us, from Ayyub, from Ibn Sirin, from Abu Hurairah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "Indeed, there is an hour in Friday; no Muslim servant coincides with it while asking Allah for something, except that He gives it to him."