Columbia subject headings:
Economics in literature.
Economics--United States--History--19th century.
Economics.
Thoreau, Henry David, 1817-1862--Knowledge and learning.
Harvard subject headings:
Economics in literature.
Economics--United States--History--19th century.
Thoreau, Henry David, 1817-1862--Knowledge--Economics.
Princeton subject headings:
Economics in literature.
Economics--United States--History--19th century.
Thoreau, Henry David, 1817-1862--Knowledge--Economics.