Musnad Ahmad 1153:859

Ya'mar ibn Bishr narrated to us, he said: Abdullah narrated to us, Yunus informed us, from Ibn Shihab, from Urwah, from Aisha, she said: We went out with the Messenger of Allah (peace and blessings of Allah be upon him) during the Farewell Pilgrimage. Some of us entered into the state of ihram for Hajj, and some of us entered into the state of ihram for Umrah, and he (the Prophet) brought a sacrificial animal. The Prophet (peace and blessings of Allah be upon him) said: "Whoever entered into the state of ihram for Umrah and did not bring a sacrificial animal, let him exit the state of ihram. Whoever entered into the state of ihram for Umrah and brought a sacrificial animal, let him not exit the state of ihram. And whoever entered into the state of ihram for Hajj, let him complete his Hajj." Aisha said: And I was among those who entered into the state of ihram for Umrah.