The Book of Pilgrimage (Kitab Al-Hajj)
Muslim :: Book 7 : Hadith 2831
'Imran b. Husain said: There was revealed the verse of Tamattu' in Hajj in the Book of Allah and the Messenger of Allah (may peace be upon him) commanded us to perform it. and then no verse was revealed abrogating the Tamattu' (form of Hajj), and the Messenger of Allah (may peace be upon him) did not forbid to do it till he died. So whatever a person said was his personal opinion. A hadith like this is transmitted on the authority of Imran b. Husain, but with this variation that he ('Imran) said: We did that (Tamattu') in the company of Allah's Messenger (may peace be upon him) and he did not say anything but he (the Holy Prophet) commanded us to do it.