Musnad Ahmad 1153:481

Husayn ibn Muhammad narrated to us, Ayyub ibn Utbah narrated to us, from Yahya, from Abu Salamah, from Aisha, who said: When the Messenger of Allah (peace and blessings of Allah be upon him) intended to marry off any of his daughters, he would sit by her curtain and say: "So-and-so mentions such-and-such," naming her and naming the man who mentions her. If she remained silent, he would marry her off. If she disliked it, she would tap the curtain, and if she tapped it, he would not marry her off.