Information on differentia
In the original Cantus index for this manuscript, differentiae were identified by a two-character code, whereby the first character indicated the last pitch of the differentia and an arbitrarily-assigned number distinguished between differentiae that ended on the same note within a mode.
Klugseder, Robert. Inventory of München, Bayerische Staatsbibliothek, Clm 4306. Edited by Debra Lacoste. 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: Cantus Planus, Universität Regensburg