Columbia subject headings:
Harvard subject headings:
Duets (Unspecified instruments (2))--Scores.
Madrigals, Italian.
Vocal duets, Unaccompanied.
Princeton subject headings:
Duets (Unspecified instruments (2))--Scores.
Madrigals (Music)
Madrigals, Italian.
Scores.
Vocal duets, Unaccompanied--Scores.