Musnad Ahmad 32:177

Isma'il narrated to us, Ayyub informed us, from Ibn Sirin, who said: Anas ibn Malik was asked: "Did the Messenger of Allah, may Allah bless him and grant him peace, perform Qunut?" He said: "Yes, after the bowing." Then he was asked after that another time: "Did the Messenger of Allah, may Allah bless him and grant him peace, perform Qunut in the morning prayer?" He said: "Yes, after the bowing, for a short while."