Musnad Ahmad 32:1887

'Affan narrated to us, Wuhayb ibn Khalid narrated to us, Ayyub narrated to us, from Abu Qilabah, from Anas, who said: "The Messenger of Allah (peace and blessings of Allah be upon him) prayed Dhuhr in Medina as four units, and he prayed Asr at Dhu al-Hulayfah as two units, and he spent the night there until morning. When he prayed the morning prayer, he mounted his riding beast. When it rose with him, he glorified Allah (said SubhanAllah) and magnified Him (said Allahu Akbar) until it reached the desert plain with him, then he combined them (the prayers). When we arrived in Mecca, the Messenger of Allah (peace and blessings of Allah be upon him) commanded them to exit the state of Ihram. When it was the Day of Tarwiyah, they entered into the state of Ihram for Hajj. The Messenger of Allah (peace and blessings of Allah be upon him) slaughtered seven camels by his own hand while they were standing. And the Messenger of Allah (peace and blessings of Allah be upon him) sacrificed in Medina two horned, black-and-white rams."