Abu Dawud Book 2, Hadith Number 1298.
Chapter : Prayer after the night prayer.
Narated By ‘Aisha, Ummul Mu’minin : Shurayh ibn Hani said: I asked ‘Aisha about the prayer of the Apostle of Allah (PBUH). She said: The Apostle of Allah (PBUH) never offered the night prayer and thereafter came to me but he offered four or six rak’ahs of prayer. One night the rain fell, so we spread a piece of leather (for his prayer), and now I see as if there is a hole in it from which the water is flowing. I never saw him protecting his clothes from the earth (as he did on that occasion).Complete Translation of Sunan Abu-Dawud, Book 2: Prayer (Kitab Al-Salat): Prayer at Night