Musannaf Ibn Abi Shayba 3:1500

Abu Bakr narrated to us, he said: Hushaym narrated to us, he said: Yunus informed us, from al-Hasan, from Abdullah ibn Mughaffal al-Muzani, who said: The Messenger of Allah (may Allah bless him and grant him peace) said: "Pray in the resting places of sheep, and do not pray in the resting places of camels, for they were created from the devils."