Musannaf Ibn Abi Shayba 18:881

Abu Bakr narrated to us, he said: Muhammad ibn Bakr narrated to us, from Ibn Jurayj, he said: I heard ‘Ata’ saying: If the one who kills by mistake leaves behind a blood money (diyah) for the one he killed, then he only has a third of it; it is only from wealth that is bequeathed.