Columbia subject headings:
Harvard subject headings:
Mexico--Social conditions--1970---Pictorial works.
Mexico--Social life and customs--Pictorial works.
Poor--Mexico--Pictorial works.
Working class--Mexico--Pictorial works.
Princeton subject headings:
Mexico--Social conditions--1970---Pictorial works.
Mexico--Social life and customs--Pictorial works.
Poor--Mexico--Pictorial works.
Working class--Mexico--Pictorial works.