Uthman bin Amr bin Aws reports this statement of his father: I came to the Prophet (peace and blessings be upon him) as part of the delegation of Thaqif. The Prophet (peace and blessings be upon him) used to come out to us and talk with us. One night he was late in coming to us, so we said: "O Messenger of Allah! You were late in coming to us tonight." The Prophet (peace and blessings be upon him) said: "I was reciting the portion of the Qur'an that I (regularly) recite, and I disliked leaving it in the middle before finishing it." When morning came, we asked the Companions of the Prophet (peace and blessings be upon him): "How do you divide the Qur'an into portions?" They replied: "Into three, five, seven, nine, eleven and thirteen; and (making) the part from 'Qaf, wal-Qur'an al-Majid' to the end of the Mufassal (one's daily portion) is good."
Al-Tabarani recorded it in al-Mu'jam al-Kabir, and he says: Al-Walid bin Muslim narrated it like this, while Waki' differed from him; and Ibn Tammam and others narrated it from Abdullah bin Abd al-Rahman, from Uthman bin Abdullah bin Aws, from his grandfather Sayyiduna Aws bin Hudhayfah (may Allah be pleased with him). I did not find anyone who has given a biography of Uthman bin Amr.