Musnad Ahmad 1153:705

Yahya ibn Ishaq narrated to us, he said: Abu 'Awanah informed us, from 'Umar ibn Abi Salamah, from his father, from 'Aishah, she said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "The right of inheritance (al-wala') belongs to the one who emancipated."