Columbia subject headings:
Harvard subject headings:
Gregorian chants--History and criticism.
Music--England--York--500-1400.
Music--Manuscripts--England--York.
Music--Manuscripts--Facsimiles.
Processionals (Liturgical books)
Princeton subject headings:
Chants.
Gregorian chants.
Music--England--York--14th century.
Music--Manuscripts--Facsimiles.
Processionals (Liturgical books)