Musnad Ahmad 626:98

Hajjaj narrated to us, Shu'bah narrated to me, from Jabir al-Ju'fi, from al-Mughirah ibn Shubayl, he said: I heard him narrating from Qays ibn Abi Hazim, from al-Mughirah ibn Shu'bah: "That he stood up during the two rak'ahs (of the prayer), so the people glorified Allah (said SubhanAllah). He said: So I saw him—meaning he glorified Allah—and he proceeded. Then he prostrated two prostrations after he had finished the salutation." He said: "This is how we did with the Prophet, may Allah bless him and grant him peace." He (the narrator) was only in doubt regarding the word "glorified."