Sunan an-Nasai Book 20, Hadith 1680

أَخْبَرَنَا مُحَمَّدُ بْنُ الْمُثَنَّى، قَالَ حَدَّثَنَا مُحَمَّدٌ، قَالَ حَدَّثَنَا شُعْبَةُ، عَنْ أَبِي إِسْحَاقَ، عَنِ الأَسْوَدِ بْنِ يَزِيدَ، قَالَ سَأَلْتُ عَائِشَةَ عَنْ صَلاَةِ، رَسُولِ اللَّهِ صلى الله عليه وسلم فَقَالَتْ كَانَ يَنَامُ أَوَّلَ اللَّيْلِ ثُمَّ يَقُومُ فَإِذَا كَانَ مِنَ السَّحَرِ أَوْتَرَ ثُمَّ أَتَى فِرَاشَهُ فَإِذَا كَانَ لَهُ حَاجَةٌ أَلَمَّ بِأَهْلِهِ فَإِذَا سَمِعَ الأَذَانَ وَثَبَ فَإِنْ كَانَ جُنُبًا أَفَاضَ عَلَيْهِ مِنَ الْمَاءِ وَإِلاَّ تَوَضَّأَ ثُمَّ خَرَجَ إِلَى الصَّلاَةِ ‏.‏

It was narrated that Al-Aswad bin Yazid said:"I asked 'Aishah about the prayer of the Messenger of Allah (ﷺ). She said: 'He used to sleep during the first part of the night, then get up during the time before dawn and pray witr. Then he would go to his bed and if he needed to be intimate he would go to his wife. Then when he heard the Adhan he would get up, and if he was junub he would pour water over himself, otherwise he would perform wudu, then he would go out to the prayer