Musnad Ahmad 25:587

Surayj narrated to us, Ibn Abi al-Zinad narrated to us, from his father, from the blind Ubayd Allah ibn Abd Allah ibn Utbah ibn Mas'ud, from Ibn Abbas, who said: The Messenger of Allah (ﷺ) took as his spoils of war his sword, Dhu al-Fiqar, on the day of Badr. It is the one regarding which he saw the vision on the day of Uhud. He said: "I saw in my sword, Dhu al-Fiqar, a notch (falan), so I interpreted it as: there shall not be (falan) among you. And I saw that I was riding behind a ram, so I interpreted it as: the ram of the battalion. And I saw that I was in a fortified coat of mail, so I interpreted it as: al-Madinah. And I saw cows being slaughtered, and cows, by Allah, are good; and cows, by Allah, are good." And it was as the Messenger of Allah (ﷺ) had said.