Musannaf Ibn Abi Shayba 13:2680

Abu Bakr narrated to us, he said: Yahya bin Sa’id narrated to us, from Sufyan, from Abu al-Zubayr, from Tawus, from Ibn Abbas, who said: "The *ruqba* (conditional gift) and the *’umra* (life-interest gift) are the same." Waki’ said: "The *’umra*, the gift (*hiba*), the donation (*’atiyya*), and the bequest (*nihla*), when they are taken possession of, are permissible."