Musnad Abu Ya'la al-Mawsili 164:7

Abu al-Rabi' narrated to us, Muhammad ibn Khazim narrated to us, Sa'd ibn Tarif narrated to us, from 'Umayr ibn Ma'mun ibn Zurarah, from al-Hasan ibn 'Ali, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "The gift of the fasting person is oil and the incense burner."