Columbia subject headings:
São Francisco River Valley (Minas Gerais-Alagoas and Sergipe, Brazil)--Economic conditions.
Harvard subject headings:
São Francisco River Valley (Minas Gerais-Alagoas and Sergipe, Brazil)--Economic conditions.
São Francisco River Valley (Minas Gerais-Alagoas and Sergipe, Brazil)--Social conditions.
Princeton subject headings:
São Francisco River Valley (Minas Gerais-Alagoas and Sergipe, Brazil)--Economic conditions.