Columbia subject headings:
Geology--Colorado--Rocky Mountain National Park--Guidebooks.
Rocky Mountain National Park (Colo.)--Guidebooks.
Harvard subject headings:
Geology--Colorado--Rocky Mountain National Park--Guidebooks.
Rocky Mountain National Park (Colo.)--Guidebooks.
Princeton subject headings:
Geology--Colorado--Rocky Mountain National Park--Guidebooks.
Rocky Mountain National Park (Colo.)--Guidebooks.