Hadith 10:53
Abu Bakr narrated to us, he said: Abd al-A’la narrated to us, from Yunus, from al-Hasan, regarding a man who divorces his wife and then has intercourse with her without having called witnesses: He said: His having intercourse with her is a revocation (raj’ah), so he should call witnesses.
حدثنا أبو بكر قال نا عبد الأعلى عن يونس عن الحسن في الرجل يطلق امرأته ثم يغشاها ولم يشهد قال غشيانه لها مراجعة فليشهد