The Repertorium of Old Bulgarian Literature and Letters was conceived as an archival repository capable of encoding and preserving in SGML (and, subsequently, XML) format archeographic, paleographic, codicological, textological, and literary-historical data concerning original and translated medieval texts represented in Balkan and other Slavic manuscripts. The files are intended to serve both as documentation (fulfilling the goals of traditional manuscript catalogues) and as direct input for computer-assisted philological research. The project site, located at http://repertorium.obdurodon.org, was designed and implemented by David J. Birnbaum, Andrej Bojadžiev, Anisava Miltenova, and Diljana Radoslavova.

• Wellesz, Egon. A history of Byzantine music and hymnography. 2nd edition, reprinted with corrections. Oxford: Clarendon Press, 1962. https://ia600607.us.archive.org/25/items/EgonWelleszAHistoryOfByzantineMusicAndHymnography1961/Egon%20Wellesz-A%20History%20of%20Byzantine%20Music%20and%20Hymnography%20(1961)_text.pdf