Columbia subject headings:
National security--Europe, Northern--Congresses.
North Atlantic Treaty Organization--Congresses.
Warsaw Treaty Organization--Congresses.
Harvard subject headings:
Europe, Northern--National security--Congresses.
National security--Europe, Northern--Congresses.
North Atlantic Treaty Organization--Congresses.
Warsaw Treaty Organization--Congresses.
Princeton subject headings:
National security--Europe, Northern--Congresses.
North Atlantic Treaty Organization--Congresses.
Warsaw Treaty Organization--Congresses.