Musannaf Ibn Abi Shayba 3:1075

Abu Khalid al-Ahmar narrated to us, from Ibn Abi Arubah, from Qatadah, from Abu Nadrah, from Abu Sa’id, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "If there are three of them, then let one of them lead them in prayer, and the most entitled of them to the leadership is the one who is most proficient in recitation."