The Book Pertaining to the Turmoil and Portents of the Last Hour (Kitab Al-Fitan wa Ashrat As-Sa`ah)
Muslim :: Book 41 : Hadith 7007
Anas b. Malik reported that Allah's Messenger (may peace be upon him) said: There is never a prophet who has not warned the Ummah of that one-eyed liar; behold he is one-eyed and your Lord is not one-eyed. On his forehead are the letters k f. r. (Kafir).