Musnad Ahmad 25:798

'Affan narrated to us, Wuhayb ibn Khalid narrated to us, 'Abdullah ibn Tawus narrated to us, from his father, from Ibn 'Abbas, that the Prophet (peace and blessings of Allah be upon him) said: "Assign the fixed shares (al-fara'id) to those entitled to them, then whatever remains belongs to the nearest male relative."