Musnad Ahmad 30:3017

Yahya narrated to us, from Muhammad, Abu Salamah narrated to me, from Abu Hurairah, from the Prophet, peace and blessings of Allah be upon him, who said: "The injury caused by an animal is exempt from liability (jabbar), the well is exempt from liability (jabbar), and the mine is exempt from liability (jabbar), and in the buried treasure (rikaz) is one-fifth."