Columbia subject headings:
Automobile trailers.
Automobile travel--History.
Motels--United States--History.
Tourist camps, hostels, etc.--United States--History.
Trailer camps.
Harvard subject headings:
Automobile travel--History.
Automobile travel--United States--History.
Motels--United States--History.
Tourist camps, hostels, etc.--United States--History.
Princeton subject headings:
Automobile travel--History.
Motels--United States--History.
Tourist camps, hostels, etc.--United States--History.