Abu Dawud
Prescribed Punishments
Book Number: 033 / Hadith Number: 4442
Narated By Al-Bara' ibn Azib : I met my uncle who was carrying a standard. I asked him: Where are you going? He said: The Apostle of Allah (pbuh) has sent me to a man who has married his father's wife. He has ordered me to cut off his head and take his property.