Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) said: Sayyiduna Ali bin Abi Talib (may Allah be pleased with him) reminded us of the prayer that we used to perform behind the Prophet (peace and blessings be upon him); we have not forgotten it (the narrator is unsure; perhaps the words are:) we have not abandoned it. The narrator said: Whenever he bowed and whenever he raised his head from bowing, he said the takbir.
Imam al-Bazzar recorded it; its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2795