Musannaf Ibn Abi Shayba 3:887

Abu Bakr narrated to us, he said: Waki’ narrated to us, from Sufyan, from Hakim ibn Jubayr, from Ibrahim, from al-Aswad, who said: I did not see anyone who was more prompt in performing the Dhuhr prayer than the Messenger of Allah (may Allah bless him and grant him peace), nor Abu Bakr, nor Umar.