أَخْبَرَنَا يَحْيَى بْنُ دُرُسْتَ، قَالَ حَدَّثَنَا أَبُو إِسْمَاعِيلَ، قَالَ حَدَّثَنَا يَحْيَى، أَنَّ أَبَا سَلَمَةَ، حَدَّثَهُ عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏"‏ لاَ تُنْكَحُ الثَّيِّبُ حَتَّى تُسْتَأْذَنَ وَلاَ تُنْكَحُ الْبِكْرُ حَتَّى تُسْتَأْمَرَ ‏"‏ ‏.‏ قَالُوا يَا رَسُولَ اللَّهِ كَيْفَ إِذْنُهَا قَالَ ‏"‏ إِذْنُهَا أَنْ تَسْكُتَ ‏"‏ ‏.‏

It was narrated from Abu Hurairah that the Messenger of Allah said: "A previously married woman should not be married until her permission has been sought, and a virgin should not be married until her consent is sought." They said: "O Messenger of Allah, how does she give her permission?" He said: "Her permission is if she keeps silent." Translation Not Available

Book Ref: Sunan An Nisai Book 26 Hadith 3265
Web Ref:  Sunan An Nisai Vol 4 Book 26 Hadith 3267