Columbia subject headings:
Harvard subject headings:
Automobile travel--Yellowstone National Park--Guidebooks.
Historic sites--Yellowstone National Park--Guidebooks.
Yellowstone National Park--Guidebooks.
Princeton subject headings:
Automobile travel--Yellowstone National Park--Guidebooks.
Guidebooks.
Historic sites--Yellowstone National Park--Guidebooks.
Yellowstone National Park--Guidebooks.