Musnad Ahmad 329:36

Ya'qub narrated to us, he said: My father narrated to us, from Ibn Ishaq, he said: 'Abdullah ibn Abi Bakr narrated to me, from 'Abbad ibn Tamim al-Ansari, then al-Mazini, from 'Abdullah ibn Zayd ibn 'Asim—and he was one of his kin, and 'Abdullah ibn Zayd was among the companions of the Messenger of Allah, may Allah bless him and grant him peace, and he had witnessed Uhud with him—he said: "I saw the Messenger of Allah, may Allah bless him and grant him peace, when he prayed for rain for us; he prolonged the supplication and multiplied the asking." He said: "Then he turned toward the Qibla and turned his cloak, so he flipped it inside out, and the people turned with him."