Sahih Al Bukhari Hadith Number 1695

Narrated Al-Miswar bin Makhrama and Marwan: The Prophet (peace be upon him) set out from Medina with over one thousand of his companions (at the time of the Treaty of Hudaibiya) and when they reached Dhul-Hulaifa, the Prophet (peace be upon him) garlanded his Hadi and marked it and assumed Ihram for `Umra.

25  Hajj (Pilgrimage)
Hadith number 1695
Volume no 2
Chapter: 106 (Marking and garlanding (the Hadi) at Dhul-Hulaifa and then assuming Ihram)