MLA

Justinus, Marcus Junianus. Epitome. 0AD. https://collections.library.yale.edu/catalog/10990708.

APA, 6th edition

Justinus, M. J. (0 C.E.). Epitome [Manuscripts, Medieval Germany 9th century, Medieval and Renaissance Manuscript Fragments in Beinecke Library, Medieval and Renaissance Manuscripts in Beinecke Library]. https://collections.library.yale.edu/catalog/10990708.