Musnad Abu Ya'la al-Mawsili 3:14

Zuhayr narrated to us, Yazid bin Harun narrated to us, al-Awwam bin Hawshab informed us, from Amr bin Murrah, from Abd al-Rahman bin Abi Layla, from Ali, who said: The Messenger of Allah (peace be upon him) came to us until he placed his foot between me and Fatimah. He taught us what we should say when we go to our beds: thirty-three glorifications (tasbih), thirty-three praises (tahmid), and thirty-four exaltations (takbir). Ali said: I have not abandoned it ever since. A man said to him: Not even on the night of Siffin? Ali said: Not even on the night of Siffin.