Sahih Muslim Book 7, Hadith Number 2865.

Chapter : Garlanding the sacrificial animals, and marking them.

Ibn ‘Abbas (Allah be pleased with them) reported that Allah’s Messenger (may peace be upon him) observed the Zuhr prayer at Dhu’l-Hulaifa; then called for his she-camel and marked it on the right side of its bump, removed the blood from it, and tied two sandals round its neck. He then mounted his camel, and when it brought him up to al-Baida’, he pronounced Talbiya for the Pilgrimage.