4319Abu Dawoodحَدَّثَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، عَنْ مُحَمَّدِ بْنِ جَعْفَرٍ، عَنْ شُعْبَةَ، ك ف ر .Shu'bah said in his version:"the letters k, f, r" (are on his forehead).Reference: Sunan Abi Dawud 4317 In-book : Book 39, Hadith 27 English translation : Book 38, Hadith 4303