Musnad Ahmad 32:2040

'Affan narrated to us, Abu 'Awanah narrated to us, 'Uthman ibn al-Mughirah narrated to us, from Salim ibn Abi al-Ja'd, from Sa'd, the freed slave of al-Hasan ibn 'Ali, who said: We went out with 'Ali, and we came to Dhu al-Hulayfah. 'Ali said: "I intend to combine Hajj and 'Umrah, so whoever wishes to do that, let him say as I say." Then he pronounced the Talbiyah and said: "Labbayka bi-hajjatin wa 'umratin ma'an" (Here I am, for a Hajj and an 'Umrah together). Salim said: And Anas ibn Malik informed me, saying: "By Allah, my foot was touching the foot of the Messenger of Allah, may Allah bless him and grant him peace, and he was pronouncing the Talbiyah for both of them together."