Musnad Abu Ya'la al-Mawsili 3:45

Ubayd Allah narrated to us, Yahya ibn Sa'id narrated to us, Shu'bah narrated to us, Abu Ishaq narrated to us, from Harithah ibn Mudarrib, from Ali, who said: There was no horseman among us on the day of Badr except for al-Miqdad.