Columbia subject headings:
Harvard subject headings:
America--Discovery and exploration.
Colorado River (Colo.-Mexico)
Powell, John Wesley, 1834-1902
United States--Discovery and exploration.
White, James, 1837-
White, James, 1837-1927.
Princeton subject headings:
Colorado River (Colo.-Mexico)
Powell, John Wesley, 1834-1902.
United States--Exploring expeditions.
White, James, 1837-