Sahih Bukhari Volume 002, Book 026, Hadith Number 627.
Narated By 'Aisha : (The wife of the Prophet (p.b.u.h) We set out with the Prophet in his last Hajj and we assumed Ihram for Umra. The Prophet then said, "Whoever has the Hadi with him should assume Ihram for Hajj along with 'Umra and should not finish the Ihram till he finishes both." I was menstruating when I reached Mecca, and so I neither did Tawaf round the Ka'ba nor Tawaf between Safa and Marwa. I complained about that to the Prophet on which he replied, "Undo and comb your head hair, and assume Ihram for Hajj (only) and leave the Umra." So, I did so. When we had performed the Hajj, the Prophet sent me with my brother 'Abdur-Rahman bin Abu Bakr to Tan'im. So I performed the 'Umra. The Prophet said to me, "This 'Umra is instead of your missed one." Those who had assumed Ihram for 'Umra (Hajj-atTamattu) performed Tawaf round the Ka'ba and between Safa and Marwa and then finished their Ihram. After returning from Mina, they performed another Tawaf (between Safa and Marwa). Those who had assumed Ihram for Hajj and 'Umra together (Hajj-al-Qiran) performed only one Tawaf (between Safa and Marwa).