Musnad Ahmad

It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) said: "Give the shares of inheritance to those who are entitled to them. After all the rightful heirs have received their shares, whatever wealth remains should be given to the closest male relative of the deceased." (In the terminology of the science of inheritance, this is called "‘Asabah").