Sayyidah Aishah (may Allah be pleased with her) said: We set out with the Messenger of Allah (peace and blessings be upon him) on the twenty-fifth of Dhu al-Qa'dah, intending nothing but Hajj. When we drew near to Makkah, the Messenger of Allah (peace and blessings be upon him) ordered those who had no sacrificial animal with them to come out of ihram after performing tawaf of the House and of Safa and Marwah. She said: On the Day of Sacrifice beef was brought to us, so I asked: "What is this?" It was said: "The Messenger of Allah (peace and blessings be upon him) has slaughtered on behalf of his pure wives."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8821