Sahih Bukhari
Saying Something under Compulsion (Ikraah)
Volume: 009 / Book Number: 085 / Hadith Number: 79
Narrated 'Aisha:
I asked the Prophet, "O Allah's Apostle! Should the women be asked for their consent to their marriage?" He said, "Yes." I said, "A virgin, if asked, feels shy and keeps quiet." He said, "Her silence means her consent."