Musannaf Ibn Abi Shayba 3:955

Mu'awiyah ibn Hisham narrated to us, he said: Ibn Abi Dhi'b narrated to us, from Abu Habibah, that it reached him from Abu Ayyub al-Ansari, that he heard the Messenger of Allah (may Allah bless him and grant him peace) saying: "Perform the Maghrib prayer when the fasting person breaks his fast, hastening before the rising of the stars."