Columbia subject headings:
Harvard subject headings:
Agriculture--Economic aspects--Mexico--Zacatecas (State)
Mexicans--United States
Peasants--Mexico--Zacatecas (State)--Economic conditions.
United States--Emigration and immigration.
Zacatecas (Mexico : State)--Emigration and immigration.
Princeton subject headings:
Agriculture--Economic aspects--Mexico--Zacatecas (State).
Marginality, Social--Mexico--Zacatecas (State).
Zacatecas (Mexico : State)--Emigration and immigration--Social aspects.
Zacatecas (Mexico : State)--Social conditions.