Sahih Bukhari Volume 003, Book 027, Hadith Number 013.
Narated By Jabir bin 'Abdullah : The Prophet and his companions assumed Ihram for Hajj and none except the Prophet and Talha had the Hadi with them. 'Ali had come from Yemen and he had the Hadi with him. He ('Ali) said, "I have assumed Ihram with an intention like that of Allah's Apostle has assumed it." The Prophet ordered his companions to intend the Ihram with which they had come for 'Umra, to perform the Tawaf of the Ka'ba (and between Safa and Marwa), to get their hair cut short and then to finish their Ihram with the exception of those who had the Hadi with them. They asked, "Shall we go to Mina and the private organs of some of us are dribbling (if we finish Ihram and have sexual relations with our wives)?" The Prophet heard that and said, "Had I known what I know now, I would not have brought the Hadi. If I did not have the Hadi with me I would have finished my Ihram." 'Aisha got her menses and performed all the ceremonies (of Hajj) except the Tawaf. So when she became clean from her menses, and she had performed the Tawaf of the Ka'ba, she said, "O Allah's Apostle! You (people) are returning with both Hajj and 'Umra and I am returning only with Hajj!" So, he ordered 'Abdur Rahman bin Abu Bakr to go with her to At-Tan'im. Thus she performed 'Umra after the Hajj in the month of Dhi-l-Hijja. Suraqa bin Malik bin Ju'sham met the Prophet at Al-'Aqaba (Jamrat-ul 'Aqaba) while the latter was stoning it and said, "O Allah's Apostle! Is this permissible only for you?" The Prophet replied, "No, it is for ever (i.e. it is permissible for all Muslims to perform 'Umra before Hajj."