Musnad Abu Ya'la al-Mawsili 155:189

Kamil ibn Talhah narrated to us, Hammad ibn Salamah narrated to us, from Muhammad ibn ‘Amr, from Abu Salamah, from Abu Hurayrah: That the Prophet (peace and blessings of Allah be upon him), when he intended to prostrate, would say the takbir, then prostrate. And when he stood up from the sitting position, he would say the takbir, then stand up.