MLA

Macrobius, Ambrosius Aurelius Theodosius. Saturnalia (Fragment). 14AD. https://collections.library.yale.edu/catalog/10543843.

APA, 6th edition

Macrobius, A. A. T. (14 C.E.). Saturnalia (fragment). [Manuscripts, Medieval Italy 14th century, Medieval and Renaissance Manuscript Fragments in Beinecke Library, Medieval and Renaissance Manuscripts in Beinecke Library]. https://collections.library.yale.edu/catalog/10543843.