Hadith 10:324
Abu Bakr narrated to us, he said: Hushaym narrated to us, from Mughira, from Ibrahim, who said: Both of them are divorced. The one whom he intended by naming her is divorced, and this one is divorced by his saying to her, "You are divorced."
حدثنا أبو بكر قال نا هشيم عن مغيرة عن إبراهيم قال تطلقان جميعا تطلق التي أراد بتسميته إياها وتطلق هذه بقوله لها أنت طالق