Musnad Abu Ya'la al-Mawsili 116:17

Ahmad narrated to us, Abu Dawud narrated to us, and he said: And Hisham narrated to us, from Qatadah, from Anas, that the Prophet (may Allah bless him and grant him peace) performed Qunut for a month after the bowing (ruku'), supplicating against tribes of the Arabs, then he abandoned it.