"I heard 'Abd Allah b. al-Zubair saying on the pulpit: When the Prophet (ﷺ) finished the prayer, he used to say (at the end of the prayer): 'There is no God but Allah, Alone, Who has no partner, to Him belongs the Kingdom, to Him praise is due, and He is Omnipotent. There is no God but Allah to Whom we are sincere in devotion, even though the infidels should disapprove. To Him belongs wealth, to Him belongs grace and to Him is worthy accorded. There is no got but Allah to Whom we are sincere in devotion, even though infidels should disapprove.
Sunan Abi Dawud Book 8, Hadith 91
"Abu Dawud narrated to us, he said: Shu'ba narrated to us, from Qatadah, from Abdur-Rahman bin Abza, that
The Messenger of Allah (ﷺ) used to recite in witr: Glorify the Name of your Lord, the Most High;" and "Say: O you disbelievers!;' and 'Say: He is Allah, (the) One.' And when he said the taslim, he would say: Subhanal-Malikil-Quddus (Glory be to the Sovereign, the Most Holy) three times, elongating his words the third time."
Sunan an-Nasa'i Book 20, Hadith 144