Columbia subject headings:
Antiphonaries.
Gregorian chants.
Liber magistri.
Music--Manuscripts--Italy--Piacenza--Indexes.
Harvard subject headings:
Antiphons (Music)--Indexes.
Biblioteca capitolare (Piacenza, Italy). Manuscript. 65.
Catholic Church. Liber magistri (Ms. Liber magistri)--Indexes.
Gregorian chants--Indexes.
Music--Manuscripts--Italy--Piacenza--Indexes.
Princeton subject headings:
Antiphons (Music)--Indexes.
Gregorian chants--Indexes.