Sunan Ibn Majah, Book 5, Hadith 1232 (In-Book) ⓘ
A man asked Ibn ‘Umar: “How should I perform Witr?” He said: “Pray Witr with one Rak’ah.” He said: “I am afraid that the people will say that I am cutting the prayer short.” He said: “The Sunnah of Allah and His Messenger.” Meaning “This is the Sunnah of Allah and His Messenger.”
حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ إِبْرَاهِيمَ الدِّمَشْقِيُّ، حَدَّثَنَا الْوَلِيدُ بْنُ مُسْلِمٍ، حَدَّثَنَا الأَوْزَاعِيُّ، حَدَّثَنَا الْمُطَّلِبُ بْنُ عَبْدِ اللَّهِ، قَالَ سَأَلَ ابْنَ عُمَرَ رَجُلٌ فَقَالَ كَيْفَ أُوتِرُ قَالَ أَوْتِرْ بِوَاحِدَةٍ . قَالَ إِنِّي أَخْشَى أَنْ يَقُولَ النَّاسُ الْبُتَيْرَاءُ فَقَالَ سُنَّةُ اللَّهِ وَرَسُولِهِ . يُرِيدُ هَذِهِ سُنَّةُ اللَّهِ وَرَسُولِهِ ـ صلى الله عليه وسلم ـ .
also referenced under: Hadith 1176 (Reference) & Volume 2, Book 5, Hadith 1176 (DarusSalam)