Hadith
أَخْبَرَنَا مَحْمُودُ بْنُ غَيْلاَنَ، قَالَ حَدَّثَنَا أَبُو دَاوُدَ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ مَالِكِ بْنِ أَنَسٍ، قَالَ سَمِعْتُهُ مِنْهُ، بَعْدَ مَوْتِ نَافِعٍ بِسَنَةٍ وَلَهُ يَوْمَئِذٍ حَلْقَةٌ قَالَ أَخْبَرَنِي عَبْدُ اللَّهِ بْنُ الْفَضْلِ عَنْ نَافِعِ بْنِ جُبَيْرٍ عَنِ ابْنِ عَبَّاسٍ أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " الأَيِّمُ أَحَقُّ بِنَفْسِهَا مِنْ وَلِيِّهَا وَالْيَتِيمَةُ تُسْتَأْمَرُ وَإِذْنُهَا صُمَاتُهَا " .
It was narrated from Ibn 'Abbas that the Prophet said:"A previously married woman has more right to decide about herself (with regard to marriage) than her guardian, and an orphan girl should be consulted, and her permission is her silence
Sahih · Abu Ghuddah
Sunan an-Nasa'i 3261 ·Book 26, Hadith 66·Also available on sunnah.com·