ENOfficial
Yazid b. al-Asamm reported: Maimuna daughter of al-Harith narrated to me that Allah's Messenger (ﷺ) married her and he was not in the state of Ihram. And she (Maimuna) was my mother's sister and that of Ibn 'Abbas (Allah be pleased with them).
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا يَحْيَى بْنُ آدَمَ، حَدَّثَنَا جَرِيرُ بْنُ حَازِمٍ، حَدَّثَنَا أَبُو فَزَارَةَ، عَنْ يَزِيدَ بْنِ الأَصَمِّ، حَدَّثَتْنِي مَيْمُونَةُ بِنْتُ الْحَارِثِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم تَزَوَّجَهَا وَهُوَ حَلاَلٌ قَالَ وَكَانَتْ خَالَتِي وَخَالَةَ ابْنِ عَبَّاسٍ .
sunnah.com