Columbia subject headings:
Conservation of natural resources--United States--History.
Conservationists--United States--Biography.
Nature conservation--United States--History--20th century.
Presidents--United States--Biography.
Roosevelt, Theodore, 1858-1919.
Harvard subject headings:
Conservation of natural resources--United States--History.
Conservationists--United States--Biography
Nature conservation--United States--History--20th century.
Presidents--United States--Biography
Roosevelt, Theodore, 1858-1919.
United States--Politics and government--1901-1909.
United States--Politics and government--1909-1913.
Princeton subject headings:
Conservation of natural resources--United States--History.
Conservationists--United States--Biography.
Nature conservation--United States--History--20th century.
Presidents--United States--Biography.
Roosevelt, Theodore, 1858-1919.