Hadith 512080
Chapter 29: Divorce - كتاب الطلاق
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ عَبْدِ رَبِّهِ بْنِ سَعِيدٍ، عَنْ مُحَمَّدِ بْنِ إِبْرَاهِيمَ بْنِ الْحَارِثِ التَّيْمِيِّ، أَنَّ نُفَيْعًا، مُكَاتَبًا كَانَ لأُمِّ سَلَمَةَ زَوْجِ النَّبِيِّ صلى الله عليه وسلم اسْتَفْتَى زَيْدَ بْنَ ثَابِتٍ فَقَالَ إِنِّي طَلَّقْتُ امْرَأَةً حُرَّةً تَطْلِيقَتَيْنِ . فَقَالَ زَيْدُ بْنُ ثَابِتٍ حَرُمَتْ عَلَيْكَ .
Yahya related to me from Malik from Abdu Rabbih ibn Said from Muhammad ibn Ibrahim ibn al-Harith at-Taymi that Nufay, a mukatab of Umm Salama, the wife of the Prophet, may Allah bless him and grant him peace, asked Zayd ibn Thabit for an opinion. He said, "I have divorced my free wife twice." Zayd ibn Thabit said, "She is haram for you."
Reference Muwatta Malik 512080
USC-MSA web (English) reference : Book 29, Hadith 49