Columbia subject headings:
Colorado River (Colo.-Mexico)--Description and travel.
Grand Canyon (Ariz.)--History.
River boats--Colorado River (Colo.-Mexico)--History.
River life--Colorado River (Colo.-Mexico)--History.
Harvard subject headings:
Colorado River (Colo.-Mexico)--Description and travel.
Grand Canyon (Ariz.)--History.
River boats--Colorado River (Colo.-Mexico)--History.
River life--Colorado River (Colo.-Mexico)--History.
Princeton subject headings:
Colorado River (Colo.-Mexico)--Description and travel.
Grand Canyon (Ariz.)--History.
River boats--Colorado River (Colo.-Mexico)--History.
River life--Colorado River (Colo.-Mexico)--History.