Sahih al-Bukhari, Book 67, Hadith 72 (In-Book) ⓘ
Narrated Abu Huraira: The Prophet said, "A matron should not be given in marriage except after consulting her; and a virgin should not be given in marriage except after her permission." The people asked, "O Allah's Messenger! How can we know her permission?" He said, "Her silence (indicates her permission).
حَدَّثَنَا مُعَاذُ بْنُ فَضَالَةَ، حَدَّثَنَا هِشَامٌ، عَنْ يَحْيَى، عَنْ أَبِي سَلَمَةَ، أَنَّ أَبَا هُرَيْرَةَ، حَدَّثَهُمْ أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " لاَ تُنْكَحُ الأَيِّمُ حَتَّى تُسْتَأْمَرَ وَلاَ تُنْكَحُ الْبِكْرُ حَتَّى تُسْتَأْذَنَ ". قَالُوا يَا رَسُولَ اللَّهِ وَكَيْفَ إِذْنُهَا قَالَ " أَنْ تَسْكُتَ ".
also referenced under: Hadith 5136 (DarusSalam) & Volume 7, Book 62, Hadith 67 (USC-MSA)