Musannaf Ibn Abi Shayba 19:415

Abu Bakr narrated to us, he said: Ad-Dahhak bin Makhlad narrated to us, from Ibn Jurayj, from ‘Ata’, regarding a man who divorced his wife and called two witnesses to testify to it. Then he arrived at the village where the woman was, had intercourse with her, and acknowledged that he had had intercourse with her, but denied that he had divorced her. ‘Ata’ said: Their testimony is accepted, they are to be separated, and he is not to be subjected to the prescribed punishment (hadd).