Columbia subject headings:
Brownsville (Tex.)--Economic conditions.
Brownsville (Tex.)--History.
Brownsville (Tex.)--Politics and government.
Matamoros (Tamaulipas, Mexico)--Economic conditions.
Matamoros (Tamaulipas, Mexico)--History.
Matamoros (Tamaulipas, Mexico)--Politics and government.
Harvard subject headings:
Brownsville (Tex.)--Economic conditions.
Brownsville (Tex.)--History.
Brownsville (Tex.)--Politics and government.
Cycles.
Matamoros (Mexico)--History.
Matamoros (Tamaulipas, Mexico)--History.
Princeton subject headings:
Brownsville (Tex.)--Economic conditions.
Brownsville (Tex.)--History.
Brownsville (Tex.)--Politics and government.
Matamoros (Tamaulipas, Mexico)--Economic conditions.
Matamoros (Tamaulipas, Mexico)--History.
Matamoros (Tamaulipas, Mexico)--Politics and government.
Mexico--Relations--United States.
United States--Relations--Mexico.