Musnad Ahmad 32:1965

Hajjaj narrated to us, Shu'bah narrated to me, and Aswad bin 'Amir Shadhan said: Shu'bah narrated to us, from Qatadah, who said: I heard Anas bin Malik saying: The Messenger of Allah (ﷺ) said to a man who was driving a sacrificial camel: "Ride it." He said: "It is a sacrificial camel." He said: "Ride it." He said: "It is a sacrificial camel." He said: "Ride it, woe to you," in the third time.