Musannaf Ibn Abi Shaybah

Al-Awza'i narrates that Umar ibn Abd al-Aziz wrote regarding the man who gave all his wealth in charity to a non-heir, and then kept that wealth with himself until he died, that one third of that wealth will be given to that non-heir person.

Usman bin Aswad narrates that Hazrat Mujahid said: Whoever made a bequest in his wealth which he did not execute until his death, then it will go to that purpose.