Musannaf Ibn Abi Shayba 3:1241

Abu Bakr narrated to us, he said: Sufyan ibn 'Uyaynah narrated to us, from al-Zuhri, from Mahmud ibn al-Rabi', from 'Ubadah ibn al-Samit, attributing it to the Prophet, may Allah bless him and grant him peace, that he said: "There is no prayer for the one who does not recite the Opening of the Book (Fatihat al-Kitab)."