Mutarrif bin Abdullah said: Imran bin Husayn (may Allah be pleased with him) and I prayed with Ali bin Abi Talib (may Allah be pleased with him). He kept saying the takbir whenever he prostrated and whenever he raised his head. When he turned around, Imran bin Husayn (may Allah be pleased with him) said: He led us in a prayer like the prayer of the Messenger of Allah (peace and blessings be upon him).
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15350