Columbia subject headings:
Transportation and state--Europe--Periodicals.
Transportation--Europe--Periodicals.
Transportation--Europe--Statistics--Periodicals.
Harvard subject headings:
Transportation and state--Europe--Periodicals.
Transportation--Europe--Periodicals.
Transportation--Europe--Statistics--Periodicals.
Princeton subject headings:
Transportation and state--Europe--Periodicals.
Transportation--Europe--Periodicals.
Transportation--Europe--Statistics--Periodicals.