Musnad Abu Ya'la al-Mawsili 131:9

Muhammad ibn Bakkar narrated to us, Hafs ibn Umar, the judge of Aleppo, narrated to us, Mukhtar ibn Fulful narrated to us, from Anas ibn Malik: That the Messenger of Allah (ﷺ) prayed the obligatory prayer on the ground while sitting, and he sat for the glorification (tasbih) on the ground, and he gestured with a gesture.