Maliks Muwatta Book 25, Hadith Number 18.
Section : Using the Skin of Animals Found Dead.
Yahya related to me from Malik from Yazid ibn Abdullah ibn Qusayt from Muhammad ibn Abd ar-Rahman ibn Thawban from his mother that A’isha, the wife of the Prophet, may Allah bless him and grant him peace, said that the Messenger of Allah, may Allah bless him and grant him peace, ordered that the skins of carrion be used after they had been tanned.