Abu Dawud Book 9, Hadith Number 2819.
Chapter : On slaughter of a fallen animal.
Narated By Abu al-Ushara’ Usamah ibn Malik : Abu al-Ushara’ reported on the authority of his father: He asked: Apostle of Allah, is the slaughtering to be done only in the upper part of the breast and the throat? The Apostle of Allah (PBUH) replied: If you pierced its thigh, it would serve you.
Abu Dawud said: This is the way suitable for slaughtering an animal which has fallen into a well or runs loose.