1703An NasaiSahih (Darussalam)أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا خَالِدُ بْنُ زِيَادٍ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم صَلاَةُ اللَّيْلِ مَثْنَى مَثْنَى وَالْوَتْرُ رَكْعَةٌ وَاحِدَةٌ " It was narrated that Ibn Umar said:"The Messenger of Allah (ﷺ) said: 'Prayer at night is two by two, and witr is one rak'ah.'"Reference: Sunan an-Nasa'i 1693 In-book : Book 20, Hadith 96 English translation : Vol. 2, Book 20, Hadith 1694