Musnad Ahmad 1153:10

Hushaym narrated to us, he said: Khalid informed us, from Abdullah ibn Shaqiq, who said: I asked Aisha about the voluntary prayer of the Messenger of Allah, may Allah bless him and grant him peace. She said: "He used to pray four [rak'ahs] before Dhuhr in my house, then he would go out and lead the people in prayer, then he would return to my house and pray two [rak'ahs]. He used to lead the people in Maghrib, then return to his house and pray two [rak'ahs]. He used to lead them in Isha, then enter my house and pray two [rak'ahs]. He used to pray nine rak'ahs at night, including the Witr. He used to pray a long night standing, and a long night sitting. When he recited while standing, he would bow and prostrate while standing; and when he recited while sitting, he would bow and prostrate while sitting. And when dawn broke, he would pray two [rak'ahs], then he would go out and lead the people in the Fajr prayer."