Columbia subject headings:
Piano music--20th century--History and criticism--Congresses.
Piano--Instruction and study--History--20th century--Congresses.
Harvard subject headings:
Pianists--20th century--History and criticism--Congresses.
Piano music--20th century--Analysis, appreciation.
Piano music--Performance.
Piano--Instruction and study--History--20th century--Congresses.
Princeton subject headings: