Hadith 10:915
Abu Bakr narrated to us, he said: Jarir narrated to us, from Mughira, from Ibrahim, who said: If a man says to his wife while she is in her waiting period (idda) from him due to *ila* (oath of abstention) or divorce, "You are divorced," then that is valid upon her. But if he says, "You are divorced after your waiting period has ended," then it is nothing; he is divorcing what he does not possess.
حدثنا أبو بكر قال نا جرير عن مغيرة عن إبراهيم قال إذا قال الرجل لأمرأته وهي تعتد منه في الإيلاء أو طلاق هي طالق فإن ذلك جائز عليها فإذا قال أنت طالق بعد ما انقضت عدتها فليس بشيء يطلق ما لا يملك