Sunan Abi Dawud

Narrated Ubayy ibn Ka'b: The Messenger of Allah (ﷺ) used to observe witr with (reciting) ""Glorify the name of thy Lord, the most High"" (Surah 87), ""Say O disbelievers"" (Surah 109), and ""Say, He is Allah, the One, Allah, the eternally besought of all