Musannaf Ibn Abi Shayba 8:1351

Abu Bakr narrated to us, he said: Safwan bin Isa narrated to us, from al-Harith bin Abd al-Rahman bin Abi Dhubab, from Mujahid, from Abdullah bin Sakhbara, from Abdullah, who said: I performed Hajj with the Messenger of Allah, may Allah bless him and grant him peace, and he did not cease the Talbiyah until he reached al-Aqaba, except to intermix it with Takbir or Tahlil.