Sunan Ibn Majah, Hadith 1185 ⓘ
It was narrated that Masruq said: “I asked ‘Aishah about the Witr of the Messenger of Allah. She said: ‘He prayed Witr at every part of the night, at the beginning, in the middle and at the end, when he died (he would perform it) just before dawn.’”
حَدَّثَنَا أَبُو بَكْرِ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو بَكْرِ بْنُ عَيَّاشٍ، عَنْ أَبِي حُصَيْنٍ، عَنْ يَحْيَى بْنِ وَثَّابٍ، عَنْ مَسْرُوقٍ، قَالَ سَأَلْتُ عَائِشَةَ عَنْ وِتْرِ، رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ فَقَالَتْ مِنْ كُلِّ اللَّيْلِ قَدْ أَوْتَرَ مِنْ أَوَّلِهِ وَأَوْسَطِهِ وَانْتَهَى وِتْرُهُ حِينَ مَاتَ فِي السَّحَرِ .
also referenced under: Book 5, Hadith 1241 (In-Book) & Volume 2, Book 5, Hadith 1185 (DarusSalam)