Musnad Ahmad 33:222

Muhammad ibn Bakr narrated to us, Ibn Jurayj informed us, 'Amr ibn Dinar informed me, he said: I heard Jabir ibn 'Abdullah saying: "We went on the expedition of the Khabt, and our commander was Abu 'Ubaydah ibn al-Jarrah. We suffered severe hunger, so the sea cast out for us a whale, the like of which we had never seen, which was called 'al-'Anbar' (the ambergris whale). We ate from it for half a month. Abu 'Ubaydah took one of its bones, and a rider would pass underneath it."