Columbia subject headings:
Harvard subject headings:
Baltic States--History--Congresses.
Baltic States--Relations--Scandinavia--Congresses.
Europe, Northern--History--Congresses.
Europe, Northern--Relations--Scandinavia--Congresses.
Scandinavia--History--Congresses.
Scandinavia--Relations--Baltic States--Congresses.
Scandinavia--Relations--Europe, Northern--Congresses.
Princeton subject headings:
Baltic States--Foreign relations--Scandinavia.
Baltic States--History--Congresses.
Scandinavia--Foreign relations--Baltic States.
Scandinavia--History--Congresses.