Res Gestae
Ammianus Marcellinus
Ammianus Marcellinus. Ammianus Marcellinus, with an English translation, Vols. I-III. Rolfe, John C., translator. Cambridge, MA; London: Harvard University Press; W. Heinemann, 1935-1940 (printing).
For by engraving many kinds of birds and beasts, even of another world, in order that the memory of their achievements might the more widely reach generations of a subsequent age, they registered the vows of kings, either promised or performed.