Columbia subject headings:
Denmark--Foreign relations--Sweden.
Norway--Foreign relations--Sweden.
Sweden--Foreign relations--Denmark.
Sweden--Foreign relations--Norway.
World War, 1939-1945--Sweden.
Harvard subject headings:
Denmark--Foreign relations--Sweden.
Norway--Foreign relations--Sweden.
Sweden--Foreign relations--Denmark.
Sweden--Foreign relations--Norway.
World War, 1939-1945--Sweden.
Princeton subject headings:
Denmark--Foreign relations--Sweden.
Norway--Foreign relations--Sweden.
Sweden--Foreign relations--Denmark.
Sweden--Foreign relations--Norway.
World War, 1939-1945--Sweden.