It is narrated from Ibrahim concerning this saying of Allah Almighty: "And know that whatever you take as spoils of anything, then indeed one-fifth of it is for Allah and for the Messenger" [Surah al-Anfal: 41], that he said: The one-fifth used to be divided into five parts; one part of them was for Allah and His Messenger (peace and blessings be upon him), and the rest were divided among the others.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قسم الفيء والغنيمة / 12941