Muhammad bin al-Muthna - al-Zaman محمد بن المثنى أبو موسى - الزمن · The Book of 'Umra

"'Umra (a gift given for life) belongs to the heir."

"Any man who is given a gift on the basis of 'Umra, it belongs to him and to his descendants. It belongs to the one to whom he gave it, and it cannot be taken back by the one who gave it, because he has given a gift, and it comes to the heirs of the one to whom it was given."

"Abu Salamah bin 'Abdur-Rahman narrated to me, that Jabir told him: 'The Messenger of Allah ruled that whoever gives a lifelong gift to a man, it belongs to him and to his heirs. It belongs to the one to whom it was given, on the basis of 'Umra. It will be inherited from its recipient according to Allah's (injunctions on) inheritance and its rights.'"