Musnad Ahmad 941:79

Hushaym narrated to us, 'Abd al-Malik informed us, 'Ata' narrated to us, he said: Usamah ibn Zayd said: I was riding behind the Messenger of Allah, may Allah bless him and grant him peace, at 'Arafat. He raised his hands supplicating, and his she-camel tilted with him, and its nose-rein fell. He said: So he reached for the nose-rein with one of his hands while he was raising his other hand.