Musnad Abu Ya'la al-Mawsili 150:333

Kamil ibn Talhah narrated to us, Ibn Lahi'ah narrated to us, Ja'far ibn Rabi'ah narrated to us, from Ibn Shihab, from 'Urwah, from 'Aishah, that the Messenger of Allah (may Allah bless him and grant him peace) said: "Any woman who marries without the permission of her guardian, her marriage is void. If he has consummated with her, then she has her dowry for what he has enjoyed of her private parts. And if they dispute, then the Sultan is the guardian of the one who has no guardian."