Musnad Ahmad 435:78

Yazid ibn Harun narrated to us, he said: Hammad ibn Salamah informed us, from Abdullah ibn Muhammad ibn Aqil, from Muhammad ibn al-Hanafiyyah, he said: I heard Muawiyah ibn Abi Sufyan saying: The Messenger of Allah, peace and blessings of Allah be upon him, said: "The *Umra* (gift of a house for life) is permissible for those to whom it is given."