Columbia subject headings:
Circus--Mexico--Chiapas--History.
Clowns--Mexico--Chiapas--History.
Harvard subject headings:
Circus--Mexico--Chiapas--History.
Clowns--Mexico--Chiapas--History.
Princeton subject headings:
Circus--Mexico--Chiapas--History.
Clowns--Mexico--Chiapas--History.