The Messenger of Allah ﷺ used to pray thirteen rak'ahs during the night, observing a witr out of that with five, he did not sit during the five except the last and then gave the salutation. Abu Dawud said: Ibn Numair reported it from Hisham recently. (Using translation from Abū Dāʾūd 1338)   

«أَنَّ رَسُولَ اللَّهِ ﷺ كَانَتْ صَلَاتُهُ مِنَ اللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ مِنْهَا بِخَمْسٍ لَا يَجْلِسُ فِي شَيْءٍ مِنَ الْخَمْسِ حَتَّى يَجْلِسَ فِي الْآخِرَةِ فَيُسَلِّمَ»  

[Machine] The Messenger of Allah ﷺ said, "Perform the Witr prayer with five (rak'ahs). If you are unable, then perform it with three (rak'ahs). If you are unable, then with one (rak'ah). And if you are unable, then make a gesture by nodding your head."  

رَسُولُ اللَّهِ ﷺ «أَوْتِرْ بِخَمْسٍ فَإِنْ لَمْ تَسْتَطِعْ فَبِثَلَاثٍ فَإِنْ لَمْ تَسْتَطِعْ فَبِوَاحِدَةٍ فَإِنْ لَمْ تَسْتَطِعْ فَأَوْمِئ ْ إِيمَاءً»  

This tradition has also been narrated on the authority of ‘A’ishah through a different chain. (Using translation from Abū Dāʾūd 99)  

عَنِ النَّبِيِّ ﷺ نَحْوَهُ  

[Machine] A man asked the Messenger of Allah ﷺ about the night prayer. He replied, "It is done in pairs. And when one of you fears the dawn, he should perform one more unit of prayer to complete what he has offered." Abu Muhammad was asked, "Do you adhere to it?" He replied, "Yes."  

سَأَلَ رَجُلٌ رَسُولَ اللَّهِ ﷺ عَنْ صَلَاةِ اللَّيْلِ فَقَالَ «مَثْنَى مَثْنَى فَإِذَا خَشِيَ أَحَدُكُمُ الصُّبْحَ فَلْيُصَلِّ رَكْعَةً وَاحِدَةً تُوتِرُ مَا قَدْ صَلَّى» قِيلَ لِأَبِي مُحَمَّدٍ تَأْخُذُ بِهِ؟ قَالَ «نَعَمْ»  

[Machine] The translation of the given text is: "The Messenger of Allah ﷺ used to pray eleven units of prayer from the night prayer (Isha) until the dawn prayer (Fajr). He would make the tasleem (conclude the prayer) after every two units, and he would perform one unit of Witr prayer."  

«كَانَ رَسُولُ اللَّهِ ﷺ يُصَلِّي مَا بَيْنَ الْعِشَاءِ إِلَى الْفَجْرِ إِحْدَى عَشْرَةَ رَكْعَةً يُسَلِّمُ فِي كُلِّ رَكْعَتَيْنِ وَيُوتِرُ بِوَاحِدَةٍ»  

“The Messenger of Allah ﷺ used to perform Witr and recite: ‘Glorify the Name of your Lord the Most High.’, [Al-A’la (87)] ‘Say: O you disbelievers!” [Al-Kafirun (109)] and ‘Say: Allah is One.”. [Al-Ikhlas (112)] (Using translation from Ibn Mājah 1171)   

«كَانَ النَّبِيُّ ﷺ يُوتِرُ بِثَلَاثٍ بِسَبِّحِ اسْمَ رَبِّكَ الْأَعْلَى وَقُلْ يَا أَيُّهَا الْكَافِرُونَ وَقُلْ هُوَ اللَّهُ أَحَدٌ»