صحيح مسلم

Ibn `Abbas reported: I spent one night in the house of my mother's sister Maimuna, daughter of Al-Harith, and said to her: Awake me when the Messenger of Allah (ﷺ) stands to pray (at night). (She woke me up when) the Messenger of Allah (ﷺ) stood up for prayer. I stood on his left side. He took hold of my hand and made me stand on his right side, and whenever I dozed off he took hold of my earlobe (and made me alert). He (the narrator) said: He (the Holy Prophet) observed eleven rak`ahs. He then sat with his legs drawn and wrapped in his garment and slept so that I could hear his breathing while asleep. And when the dawn appeared, he observed two short rak`ahs of (Sunnah) prayer.