Musnad Ahmad 329:6

I read to Abd al-Rahman: Malik, from Abdullah ibn Abi Bakr, that he heard Abbad ibn Tamim say: I heard Abdullah ibn Zayd al-Mazini say: "The Messenger of Allah, peace and blessings of Allah be upon him, went out to the prayer ground (al-musalla) and sought rain, and he turned his cloak around when he faced the qibla."