Musnad Ahmad 482:163

Hajjaj narrated to us, Laith narrated to us, Yazid ibn Abi Habib narrated to me, from Abu Imran, from Uqbah ibn Amir, that he said: I followed the Messenger of Allah, peace and blessings of Allah be upon him, while he was riding, and I placed my hand on his foot. I said: "Teach me Surah Hud or Surah Yusuf." He said: "You will never recite anything more reaching to Allah than 'Say, I seek refuge in the Lord of the daybreak.'"