Sahih Muslim
The Book of Vision (Kitab Al-Ruya)
Book Number: 029 / Hadith Number: 5636
Abu Huraira reported: I heard Allah's Messenger (may peace be upon him) as saying: He who saw me in a dream would soon see me in the state of wakefulness, or as if he saw me in a state of wakefulness, for the satan does not appear in my form.