Sahih al-Bukhari 5319
Narrated `Abdullah bin `Abdullah:
that his father had written to Ibn Al-Arqam a letter asking him to ask Subai'a Al-Aslamiya how the 
Prophet had given her the verdict. She said, "The Prophet, gave me his verdict that after I gave birth, I 
could marry."
حَدَّثَنَا يَحْيَى بْنُ بُكَيْرٍ، عَنِ اللَّيْثِ، عَنْ يَزِيدَ، أَنَّ ابْنَ شِهَابٍ، كَتَبَ إِلَيْهِ أَنَّ عُبَيْدَ اللَّهِ بْنَ عَبْدِ اللَّهِ، أَخْبَرَهُ عَنْ أَبِيهِ، أَنَّهُ كَتَبَ إِلَى ابْنِ الأَرْقَمِ أَنْ يَسْأَلَ، سُبَيْعَةَ الأَسْلَمِيَّةَ كَيْفَ أَفْتَاهَا النَّبِيُّ صلى الله عليه وسلم فَقَالَتْ أَفْتَانِي إِذَا وَضَعْتُ أَنْ أَنْكِحَ‏.‏