Musnad Abu Ya'la al-Mawsili 108:48

Abu Bakr ibn Abi Shaybah narrated to us, Abu Khalid al-Ahmar narrated to us, from Ibn Jurayj, from Abu al-Zubayr, from Jabir, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Ride the sacrificial animals (al-hady) in a reasonable manner until you find a mount."