Columbia subject headings:
Catholic Church. Gradual (Pre-Vatican II)
Early printed books--Italy--Venice--16th century.
Graduals (Liturgical books)--Indexes.
Gregorian chants.
Music publishing--Italy--Venice--History--16th century.
Harvard subject headings:
Catholic Church. Gradual (Pre-Vatican II)
Catholic Church. Gradual (Pre-Vatican II)--Indexes.
Early printed books--Italy--Venice--16th century.
Graduals (Liturgical books)--History.
Graduals (Liturgical books)--Indexes.
Music publishing--Italy--Venice--History--16th century.
Princeton subject headings: