Musnad Ahmad 33:954

Muhammad ibn Bakr narrated to us, Ibn Jurayj informed us, Abu al-Zubayr informed me that he heard Jabir ibn Abdullah al-Ansari saying: "I saw the Prophet, peace and blessings of Allah be upon him, while he was upon his riding beast, praying the voluntary prayers in every direction. However, he would lower the two prostrations of the rak'ah, and he would gesture with a gesture."