Columbia subject headings:
Conservationists--United States--Biography.
Muir, John, 1838-1914.
Naturalists--United States--Biography.
Nature conservation--United States--History.
Harvard subject headings:
Conservationists--United States--Biography
Muir, John, 1838-1914
Naturalists--United States--Biography
Nature conservation--United States--History
Princeton subject headings:
Conservationists--United States--Biography.
Muir, John, 1838-1914.
Naturalists--United States--Biography.
Nature conservation--United States--History.