Sahih Muslim
The Book Pertaining to Punishments Prescribed by Islam (Kitab Al-Hudud)
Book Number: 017 / Hadith Number: 4242
Abu Huraira reported Allah's Messenger (may peace be upon him) as saying: The wound caused (by falling) in the well, in the mine, and caused bv the animal has no requital for it; and there is one-fifth (for the government) in the buried treasure.