Columbia subject headings:
Thoreau, Henry David, 1817-1862.
Harvard subject headings:
Authors, American--19th century--Biography
Intellectuals--United States--Biography.
Naturalists--United States--Biography
Thoreau, Henry David, 1817-1862
Princeton subject headings:
Authors, American--19th century--Biography.
Thoreau, Henry David, 1817-1862.