(1) باب التَّطَوُّعِ وَرَكَعَاتِ السُّنَّةِ
Narrated Abd Allah b. Shaqiq:
I asked A'ishah about the voluntary prayers offered by the Messenger of Allah (ﷺ). She replied: Before the noon prayer he would pray four rak'ahs in my house, then go out and lead the people in prayer, then return to my house and pray two rak'ahs. He would lead the people in the sunset prayer, then return to my house and pray two rak'ahs. Then he would lead the people in the night prayer, and enter my house and pray two rak'ahs. He would pray nine rak'ahs during the night, including witr (prayer). At night he would pray for a long time standing and for a long time sitting. When he recited the Qur'an while standing, he would bow and prostrate himself from the standing position, and when he recited while sitting, he would bow and prostrate himself from the sitting position, and when dawn came he prayed two rak'ahs, then he would come out and lead the people in the dawn prayer.
Reference: Sunan Abi Dawud 1251
In-book reference: Book 5, Hadith 2
English translation: Book 5, Hadith 1246