Narrated Anas:
that the Prophet (ﷺ), Abu Bakr, and 'Umar - and I think he said - and 'Uthman would recite: "Maaliki Yawmid-Din (1:4).'" (FR)
English reference (FR): Vol. 5, Book 43, Hadith 2928 (FR)
Arabic reference (FR): Book 46, Hadith 3178 (FR)