Lectionary
MLA
Church, Catholic. Lectionary. St. Cecilia, 0AD. https://collections.library.yale.edu/catalog/2004994.
APA, 6th edition
Church, C. (0 C.E.). Lectionary [Manuscripts, Medieval--Italy--11th century, Marginalia, Musical works, Rubrics]. St. Cecilia. https://collections.library.yale.edu/catalog/2004994.