Musnad Ahmad 27:1401

'Affan narrated to us, 'Abd al-'Aziz bin Muslim narrated to us, 'Abdullah bin Dinar narrated to us, from Ibn 'Umar, who said: The Messenger of Allah (ﷺ) said: "Indeed, Bilal calls the Adhan at night, so eat and drink until Ibn Umm Maktum calls the Adhan."