Abu Dawud Book 33, Hadith Number 4420.

Narated By Buraydah ibn al-Hasib : We, the Companions of the Apostle of Allah (PBUH), used to talk mutually: Would that al-Ghamidiyyah and Ma’iz ibn Malik had withdrawn after their confession; or he said: Had they not withdrawn after their confession, he would not have pursued them (for punishment). He had them stoned after the fourth (confession).