The Book of Pilgrimage (Kitab Al-Hajj)

Muslim :: Book 7 : Hadith 2861

Ibn 'Abbas (Allah be pleased with them) reported: Allah's Messenger (may peace be upon him) came along with his Companions when four days had passed out of ten days (of Dhu'l-Hijja) and they were pronouncing Talbiya for Hajj, and he (the Holy Prophet) commanded them to change (this Ihram) into that of 'Umra.

Source materials are from the University of Southern California MSA site
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