Sunan Ibn Majah 1964
سنن ابن ماجه#1964SahihMaimunah bint Harith narrated:that the Messenger of Allah married her when he was Halal (not in Ihram). (Sahih).He (one of the narrators-Yazid) said: "And she was my maternal aunt and the maternal aunt of Idn 'Abbas also
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Zubair Ali ZaiSahih Muslim
In-book reference: 9:120