Maliks Muwatta Book 023, Hadith Number 004.

Section : Prohibition against Sacrificing an Animal Before the Imam Departs.

Yahya related to me from Malik from Yahya ibn Said from Bushayr ibn Yasar that Abu Burda ibn Niyar sacrificed an animal before the Messenger of Allah, may Allah bless him and grant him peace, sacrificed on the Day of Sacrifice. He asserted that the Messenger of Allah, may Allah bless him and grant him peace, ordered him to sacrifice another animal, and he, Abu Burda, said, "What if I can only find an animal less than one year old, Messenger of Allah?" He had said, "If you can only find a young animal, then sacrifice it."