Sunan an Nasai
2682
Sahih+2

It was narrated from 'Abdullah bin 'Umar that his sister, Hafsah, said; "I said to the Prophet;'O Messenger of Allah! Why is it that the people have exited Ihram and you have not exited Ihram following your 'Umrah?'He said:'I have matted my hair and garlanded my Hadi (sacrificial animal), so I will not exit Ihram until I exit Ihram after Hajj

SahihAbu Ghuddah
SahihAl-Albani