Sahih Bukhari | Volume 5 | Hadith Number 690

We set out with Allah's Apostle, and some of us assumed the ihram for 'Umra, some assumed it for Hajj, and some assumed it for both Hajj and 'Umra. Allah's Apostle assumed the Ihram for Hajj. So those who had assumed the Ihram for Hajj or for both Hajj and 'Umra, did not finish their Ihram till the day of An-Nahr (i.e. slaughter of sacrifices).