Maimunah 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." (ES)
English reference (ES): Vol. 3, Book 9, Hadith 1964 (ES)
Arabic reference (ES): Book 9, Hadith 2040 (ES)