Musnad Abu Ya'la al-Mawsili 110:138

Ibrahim ibn al-Hajjaj narrated to us, Wahib narrated to us, from Ibn Tawus, from Ikrimah ibn Khalid, from Ibn Abbas, that he spent the night at his maternal aunt Maymunah’s house. The Prophet, may Allah bless him and grant him peace, stood up during the night and prayed. He said: So I stood on his left, and he pulled me until he placed me on his right. He said: Then he prayed thirteen rak'ahs, his standing in them being equal.