وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، عَنْ عَبْدِ اللَّهِ بْنِ عُمَرَ، أَنَّهُ كَانَ يَقُولُ إِذَا طَلَّقَ الرَّجُلُ امْرَأَتَهُ فَدَخَلَتْ فِي الدَّمِ مِنَ الْحَيْضَةِ الثَّالِثَةِ فَقَدْ بَرِئَتْ مِنْهُ وَبَرِئَ مِنْهَا ‏.‏ قَالَ مَالِكٌ وَهُوَ الأَمْرُ عِنْدَنَا ‏.‏

Yahya related to me from Malik from Nafi that Abdullah ibn Umarsaid, "When a man divorces his wife and she begins her third period,she is free from him and he is free from her." Malik said,"This is how things are done among us." Translation Not Available

Book Ref: Muwatta Imam Malik Book 29 Hadith 1219
Web Ref:  Muwatta Imam Malik Book 29 Hadith 58