Sahih Muslim Book 4, Hadith Number 1774.

Chapter : Excellence of the recitation of “Say: He is Allah, the One”.

‘Uqba b. ‘Amir reported Allah’s Messenger (may peace be upon him) as saying: What wonderful verses have been sent down today, the like of which has never been seen ! They are: “Say: I seek refuge with the Lord of the dawn,” and “Say: I seek refuge with the Lord of men.”