Sahih Bukhari, Chapter: Pilgrimage (Hajj)

Abdullah (bin Abdullah) bin Umar said to his father, "Stay here, for I am afraid that it (affliction between Ibn Zubair and Al-Hajjaj) might prevent you from reaching the Kaaba." Ibn 'Umar said, "(In this case) I would do the same as Allah's Apostle did, and Allah has said, 'Verily, in Allah's Apostle, you have a good example (to follow).' So, I make you, people, witness that I have made Umra compulsory for me." So he assumed lhram for Umra. Then he went out and when he reached Al-Baida, he assumed Ihram for Hajj and Umra (together) and said, "The conditions (requisites) of Hajj and Umra are the same." He, then brought a Hadi from Qudaid. Then he arrived (at Mecca) and performed Tawaf (between Safa and Marwa) once for both Hajj and Umra and did not finish the lhram till he had finished both Hajj and Umra.