Columbia subject headings:
Harvard subject headings:
National parks and reserves--United States--History
Parks--Government policy--United States--History.
United States. National Park Service--Officials and employees--Biography.
Wirth, Conrad Louis, 1899-
Princeton subject headings:
National parks and reserves--United States--History.
Parks--Government policy--United States--History.
United States. National Park Service--Officials and employees--Biography.
Wirth, Conrad Louis, 1899-1993.