Musnad Ahmad 32:1207

Rawh narrated to us, Ash'ath narrated to us, from al-Hasan, from Anas ibn Malik, that he said: "I have not prayed behind anyone after the Messenger of Allah, peace and blessings of Allah be upon him, who was more concise in prayer, nor more complete, than the Messenger of Allah, peace and blessings of Allah be upon him."