Columbia subject headings:
Music theory--Early works to 1800.
Music, Greek and Roman--History and criticism--Early works to 1800.
Ptolemy, active 2nd century. Harmonics.
Harvard subject headings:
Music theory--Early works to 1800.
Music, Greek and Roman--History and criticism--Early works to 1800.
Ptolemy, active 2nd century. Harmonics.
Princeton subject headings:
Music theory--Early works to 1800.
Music, Greek and Roman--History and criticism--Early works to 1800.