Columbia subject headings:
Local transit--France--Paris Metropolian Area--History.
Régie autonome des transports parisiens--History.
Harvard subject headings:
Local transit--France--Paris Metropolitan Area--History.
Régie autonome des transports parisiens--History.
Princeton subject headings:
Local transit--France--Paris Metropolitan Area--History.
Régie autonome des transports parisiens--History.