Columbia subject headings:
Music theory--History--16th century.
Organ (Musical instrument)--Instruction and study.
Harvard subject headings:
Music theory--Early works to 1800.
Music theory--History--16th century.
Organ (Musical instrument)--Instruction and study--Early works to 1800.
Princeton subject headings:
Music theory--Early works to 1800.
Organ (Musical instrument)--Instruction and study--Early works to 1800.