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 اللهِ ﷺ كَانَتْ صَلَاتُهُ مِنَ اللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ بِخَمْسٍ وَلَا يُسَلِّمُ فِي شَيْءٍ مِنَ الْخَمْسِ حَتَّى يَجْلِسَ فِي الْآخِرَةِ ثُمَّ يُسَلِّمَ  

[Machine] The Messenger of Allah ﷺ used to pray thirteen rak'ahs at night, in which he would perform the witr prayer with five rak'ahs. He would not sit during any of them until he sat in the last one. According to the narration of Ibrahim ibn Musa, he would conclude his prayer with the saying of "as-salamu alaykum" (peace be upon you). In the narration of Abu Bakr, the prayer of the Messenger of Allah ﷺ at night consisted of thirteen rak'ahs, in which he would perform the witr prayer with five rak'ahs. He would not sit during any of them except for the last one.  

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ مِنْهَا بِخَمْسٍ وَلَا يَجْلِسُ فِي شَيْءٍ مِنْهَا حَتَّى يَجْلِسَ فِي آخِرِهِنَّ فَيُسَلِّمَ لَفْظُ حَدِيثِ إِبْرَاهِيمَ بْنِ مُوسَى وَفِي رِوَايَةِ أَبِي بَكْرٍ كَانَتْ صَلَاةُ رَسُولِ اللهِ ﷺ بِاللَّيْلِ ثَلَاثَ عَشْرَةَ رَكْعَةً يُوتِرُ مِنْ ذَلِكَ بِخَمْسٍ لَا يَجْلِسُ فِي شَيْءٍ مِنْهَا إِلَّا فِي آخِرِهَا  

[Machine] The Messenger of Allah ﷺ used to lie down, and when he woke up, he would rinse his mouth with water (Miswak), then perform ablution (Wudu), then pray eight units of prayer. He would sit after every two units and make the Tasleem (saying "As-salamu alaykum" to end the prayer), then he would pray five units of Witr prayer. He would not sit except in the fifth unit, and he would not make the Tasleem except in the fifth unit, and he would repeat this process.  

أَنَّ رَسُولَ اللهِ ﷺ كَانَ يَرْقُدُ فَإِذَا اسْتَيْقَظَ تَسَوَّكَ ثُمَّ تَوَضَّأَ ثُمَّ صَلَّى ثَمَانِ رَكَعَاتٍ يَجْلِسُ فِي كُلِّ رَكْعَتَيْنِ وَيُسَلِّمُ ثُمَّ يُوتِرُ بِخَمْسِ رَكَعَاتٍ لَا يَجْلِسُ إِلَّا فِي الْخَامِسَةِ وَلَا يُسَلِّمُ إِلَّا فِي الْخَامِسَةِ وَهَكَذَا  

The Messenger of Allah ﷺ used to pray thirteen rak'ahs, observing six rak'ahs in pairs including the two rak'ahs of dawn prayer. He would observe witr and five rak'ahs. He sat only in the last of them. (Using translation from Abū Dāʾūd 1359)   

كَانَ رَسُولُ اللهِ ﷺ يُصَلِّي ثَلَاثَ عَشْرَةَ رَكْعَةً بِرَكْعَتَيْهِ قَبْلَ الصُّبْحِ يُصَلِّي سِتًّا مَثْنَى مَثْنَى وَيُوتِرُ بِخَمْسٍ لَا يَقْعُدُ بَيْنَهُنَّ إِلَّا فِي آخِرِهِنَّ  

كَانَ رَسُولُ اللهِ ﷺ يُوتِرُ بِثَلَاثٍ لَا يَقْعُدُ إِلَّا فِي آخِرِهِنَّ كَذَا فِي هَذِهِ الرِّوَايَةِ وَقَدْ رُوِّينَا فِي حَدِيثِ سَعْدِ بْنِ هِشَامٍ وِتْرَ النَّبِيِّ ﷺ بِتِسْعٍ ثُمَّ بِسَبْعٍ وَاللهُ أَعْلَمُ  

[Machine] Aisha, may Allah be pleased with her, was asked, "How did the Messenger of Allah ﷺ perform his Witr prayer?" She replied, "He used to perform Witr with four rak'ahs, then three, then two, then one. He would not increase it more than thirteen rak'ahs, according to Ahmad's narration. He did not perform two rak'ahs before Fajr prayer." I asked, "What is Witr prayer?" She said, "He did not leave this practice, and Ahmad did not mention three and six. This could possibly mean that it refers to three rak'ahs that are not separated by sitting or saying taslim, which would be similar to the narration of Hisham ibn 'Urwah. Allah knows best. We have also narrated from Abdullah ibn Abbas from the Prophet ﷺ with the same meaning as Hisham ibn 'Urwah's narration about Witr prayer, consisting of five rak'ahs."  

لِعَائِشَةَ ؓ بِكُمْ كَانَ رَسُولُ اللهِ ﷺ يُوتِرُ؟ قَالَتْ كَانَ يُوتِرُ بِأَرْبَعٍ وَثَلَاثٍ وَسِتٍّ وَثَلَاثٍ وَثَمَانٍ وَثَلَاثٍ وَعَشْرٍ وَثَلَاثٍ وَلَمْ يَكُنْ يُوتِرُ بِأَنْقَصَ مِنْ سَبْعٍ وَلَا بِأَكْثَرَ مِنْ ثَلَاثِ عَشْرَةَ زَادَ أَحْمَدُ وَلَمْ يَكُنْ يُوتِرُ بِرَكْعَتَيْنِ قَبْلَ الْفَجْرِ قُلْتُ مَا يُوتِرُ؟ قَالَتْ لَمْ يَكُنْ يَدَعْ ذَلِكَ وَلَمْ يَذْكُرْ أَحْمَدُ وَسِتٍّ وَثَلَاثٍ وَهَذَا يَحْتَمِلُ أَنْ يُرِيدَ بِهِ ثَلَاثًا لَا يَفْصِلُ بَيْنَهُنَّ بِجُلُوسٍ وَلَا تَسْلِيمٍ فَيَكُونُ فِي مَعْنَى رِوَايَةِ هِشَامِ بْنِ عُرْوَةَ وَاللهُ أَعْلَمُ وَرُوِّينَا عَنْ عَبْدِ اللهِ بْنِ عَبَّاسٍ عَنِ النَّبِيِّ ﷺ بِمَعْنَى رِوَايَةِ هِشَامِ بْنِ عُرْوَةَ فِي الْوِتْرِ بِخَمْسِ رَكَعَاتٍ  

I spent a night in the house of my maternal aunt Maimunah, daughter of al-Harith. The Prophet ﷺ offered the night prayer. He then came and prayed four rak'ahs and slept. He then stood up and prayed. I stood at his left side. He made me go round and made me stand at his right side. He then prayed five rak'ahs and slept, and I heard his snoring. He then got up and prayed two rak'ahs. Afterwards he came out and offered the dawn prayer. (Using translation from Abū Dāʾūd 1357)   

بِتُّ فِي بَيْتِ خَالَتِي مَيْمُونَةَ فَصَلَّى النَّبِيُّ ﷺ الْعِشَاءَ ثُمَّ جَاءَ فَصَلَّى أَرْبَعَ رَكَعَاتٍ ثُمَّ نَامَ ثُمَّ قَامَ قَالَ فَجِئْتُ فَقُمْتُ عَنْ يَسَارِهِ فَحَوَّلَنِي عَنْ يَمِينِهِ فَصَلَّى خَمْسَ رَكَعَاتٍ ثُمَّ صَلَّى رَكْعَتَيْنِ ثُمَّ نَامَ حَتَّى سَمِعْتُ غَطِيطَهُ أَوْ قَالَ خَطِيطَهُ ثُمَّ خَرَجَ إِلَى الصَّلَاةِ  

[Machine] That Abbas bin Abd al-Muttalib sent him to the Messenger of Allah, ﷺ , for a need, and it was the night when Maymuna bint al-Harith, the aunt of Ibn Abbas, was there. So he entered upon her and found the Messenger of Allah, ﷺ , in the mosque. Ibn Abbas said, "I lay down in his room and thought to myself, how much does the Messenger of Allah, ﷺ , pray?" Then he came to me while I was lying down in the room after a third of the night had passed, and he said, "Lie down." He said again, "Then he took a cloak and covered Maymuna with part of it, and some of it was on her. Then he stood up and prayed two rak'ahs, until he prayed eight rak'ahs, then he offered the Witr prayer with five rak'ahs, without sitting between them. Then he sat down and praised Allah and praised Him abundantly. Then his last words were, "O Allah, make light in my heart, and make light in my hearing, and make light in my sight, and make light for me on my right and make light for me on my left, and make light for me ahead of me and make light for me behind me, and increase me in light and increase me in light."  

أَنَّ الْعَبَّاسَ بْنَ عَبْدِ الْمُطَّلِبِ بَعَثَهُ إِلَى رَسُولِ اللهِ ﷺ فِي حَاجَةٍ وَكَانَتْ لَيْلَةَ مَيْمُونَةَ بِنْتِ الْحَارِثِ خَالَةِ ابْنِ عَبَّاسٍ فَدَخَلَ عَلَيْهَا فَوَجَدَ رَسُولَ اللهِ ﷺ فِي الْمَسْجِدِ قَالَ ابْنُ عَبَّاسٍ فَاضْطَجَعْتُ فِي حُجْرَتِهِ فَجَعَلْتُ فِي نَفْسِي أَنْ أُحْصِيَ كَمْ يُصَلِّي رَسُولُ اللهِ ﷺ؟ فَجَاءَ وَأَنَا مُضْطَجِعٌ فِي الْحُجْرَةِ بَعْدَ أَنْ ذَهَبَ ثُلُثُ اللَّيْلِ ثُمَّ قَالَ ارْقُدْ أَوْ بَعْدُ قَالَ ثُمَّ تَنَاوَلَ مِلْحَفَةً عَلَى مَيْمُونَةَ فَارْتَدَى بِبَعْضِهَا وَعَلَيْهَا بَعْضُهَا ثُمَّ قَامَ فَصَلَّى رَكْعَتَيْنِ حَتَّى صَلَّى ثَمَانِ رَكَعَاتٍ ثُمَّ أَوْتَرَ بِخَمْسٍ لَمْ يَجْلِسْ بَيْنَهُنَّ ثُمَّ قَعَدَ فَأَثْنَى عَلَى اللهِ بِمَا هُوَ أَهْلُهُ فَأَكْثَرَ مِنَ الثَّنَاءِ ثُمَّ كَانَ آخِرُ كَلَامِهِ أَنْ قَالَ اللهُمَّ اجْعَلْ لِي نُورًا فِي قَلْبِي وَاجْعَلْ لِي نُورًا فِي سَمْعِي وَاجْعَلْ لِي نُورًا فِي بَصَرِي وَاجْعَلْ لِي نُورًا عَنْ يَمِينِي وَنُورًا عَنْ شِمَالِي وَاجْعَلْ لِي نُورًا بَيْنَ يَدِيَّ وَنُورًا خَلْفِي وَزِدْنِي نُورًا وَزِدْنِي نُورًا  

[Machine] That Zaid used to perform Witr with five (rak'ahs) and would only say the salaam in the fifth (rak'ah), and my father used to do it like that, and I found it in the book of my father, Mouqayyad.  

أَنَّ زَيْدًا كَانَ يُوتِرُ بِخَمْسٍ لَا يُسَلِّمُ إِلَّا فِي الْخَامِسَةِ وَكَانَ أَبِي يَفْعَلُهُ كَذَا وَجَدْتُهُ فِي الْكِتَابِ أَبِي مُقَيَّدًا  

[Machine] Umru was more knowledgeable than him, and he would rise at the third hour with the takbeer.  

كَانَ عُمَرُ أَفْقَهَ مِنْهُ كَانَ يَنْهَضُ فِي الثَّالِثَةِ بِالتَّكْبِيرِ  

[Machine] He used to perform a supererogatory prayer consisting of three units, in which he would neither sit nor recite the Tashahhud except in the last unit.  

أَنَّهُ كَانَ يُوتِرُ بِثَلَاثٍ لَا يَجْلِسُ فِيهِنَّ وَلَا يَتَشَهَّدُ إِلَّا فِي آخِرِهِنَّ