Sahih Bukhari
Sahih Bukhari Volume 003, Book 028, Hadith Number 038.
Hadith Section/Book: Sahih Bukhari Sahih Bukhari Book 28. Pilgrims Prevented from Completing the Pilgrimmage
Narated By Al-Miswar : Allah's Apostle slaughtered (the Hadi) before he had his head shaved and then he ordered his Companions to do the same.