Information on differentia
In the original Cantus index for this manuscript, the differentiae were identified using a two-digit system: a letter to indicate the last note of the differentia and a number to distinguish between differentiae in the same mode with the same last note.
Helsen, Kate. Inventory of Fulda, Hessische Landesbibliothek, Aa 55. Edited by Andrew Mitchell. In: Cantus Manuscript Database for Latin Ecclesiastical Chant: Inventories of Chant Sources. Directed by Debra Lacoste (2011-), Terence Bailey (1997-2010), and Ruth Steiner (1987-1996). Web developer, Jan Kolácek (2011-).
Images: Antiphonale, Fulda University and State Library