MLA

Chevalier Au Baril. 0AD. https://collections.library.yale.edu/catalog/2043575.

APA, 6th edition

Chevalier au Baril. (0 C.E.). [Manuscripts, Medieval France 13th century, Medieval and Renaissance Manuscript Fragments in Beinecke Library, Medieval and Renaissance Manuscripts in Beinecke Library]. https://collections.library.yale.edu/catalog/2043575.