Musnad Ahmad 5:744

Bahz ibn Asad narrated to us, Hammad ibn Salamah narrated to us, Salamah ibn Kuhayl informed us, from Hujayyah ibn 'Adi, that Ali was asked about the cow, and he said: "It is for seven." And he was asked about the one with a broken horn, and he said: "There is no harm in it." And he was asked about the limping one, and he said: "As long as it does not reach the place of sacrifice." Then he said: "The Messenger of Allah, may Allah bless him and grant him peace, commanded us to examine the eyes and the ears."