Sahih Muslim Book 007, Hadith Number 2853.
Chapter : One who undertakes to perform Umra is not allowed to put off Ihram before Sai' and the pilgrim and the (Qiran) is not allowed to put off ihram at Tawaf Qud'um (circumambulation of arrival).
Abdullah, the freed slave of Asma' bint Abu Bakr (Allah be pleased with them), narrated that he used to hear Asma,' whenever she passed by Hajun, saying (these words): "May there be peace and blessing of Allah upon His Messenger." We used to stay here along with him with light burdens. Few were our rides, and small were our provisions. I performed 'Umra and so did my sister 'Aisha, and Zubair and so and so. And as we touched the House (performed circumambulation and Sa'i) we put off Ihram, and then again put on Ihram in the afternoon for Hajj. Harun (one of the narrators) in one of the narrations said: The freed slave of Asma' and he did not mention 'Abdullah.