Atkinson, Charles M:
Review: Anonymous (Ninth Century): Music Handbook (Musica Enchiriadis). 1978. — 90-92.



https://bibliothekskatalog.hfmt-koeln.de/Record/ai-55-aHR0cHM6Ly93d3cuanN0b3Iub3JnL3N0YWJsZS85NDAxMDI (Datum: 08.05.2021)