´Zakariyya bin Abi Za'idah narrated from Abu Ishaq, from Sa'id bin Jubair, that Ibn Abbas said:` "The Messenger of Allah (ﷺ) used to pray witr with three rak'ahs. In the first he would recite "Glorify the Name of Your Lord, the Most High;" in the second: "Say: O You disbelievers!" and in the third: "Say: He is Allah, (the) One.'"
Hadith Referenceسنن نسائي / كتاب قيام الليل وتطوع النهار / 1703
´Zuhair narrated from Abu Ishaq, from Sa'eed bin Jubair, :` Ibn Abbas used to pray witr with three (units) with (the Surahs): "Glorify the Name of Your Lord, the Most High" (Surah Al-A'la), "Say: O You disbelievers" (Surah Al-Kafirun), and "Say: He is Allah, (the) One" (Surah Al-Ikhlas).
Hafiz Muhammad Ameen
1704. Commentary: The difference between the two is that in the first narration, three witr are mentioned as the action of the Messenger of Allah (sallallahu alayhi wa sallam), while in the second hadith, it is the personal action of Ibn Abbas (radi Allahu anhuma). By "difference," this is what the author (rahimahullah) intends. And Allah knows best.
Source: Sunan Nasa'i: Translation and Benefits by Shaykh Hafiz Muhammad Amin Hafizullah, Page: 1704