MLA

Pseudo-Isidore. Decretales (Excerpts) (Fragment). 0AD. https://collections.library.yale.edu/catalog/2004024.

APA, 6th edition

P.-I. (0 C.E.). Decretales (excerpts) (fragment). [Manuscripts, Medieval Germany 12th century, Medieval and Renaissance Manuscript Fragments in Beinecke Library, Medieval and Renaissance Manuscripts in Beinecke Library]. https://collections.library.yale.edu/catalog/2004024.