Mutarrif bin Abdullah (may Allah have mercy on him) said: Imran bin Husayn (may Allah be pleased with him) and I prayed in Kufah behind Ali bin Abi Talib (may Allah be pleased with him), and he said these takbirs when bowing and when prostrating, saying the takbir at every point. When we had finished the prayer, Imran (may Allah be pleased with him) said to me: "For a long time, or for such-and-such a time, I have not prayed a prayer more like the prayer of the Messenger of Allah (peace and blessings be upon him) than this prayer."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 15320