Columbia subject headings:
Harvard subject headings:
Baltic Sea Region--History--Congresses.
Cities and towns--Baltic Sea Region--Congresses.
Plague--Baltic Sea Region--History--Congresses.
Plague--Sweden--History--Congresses.
Princeton subject headings:
Cities and towns--Baltic Sea Region--History--17th century--Congresses.
Cities and towns--Baltic Sea Region--History--18th century--Congresses.
Urbanization--Baltic Sea Region--History--17th century--Congresses.
Urbanization--Baltic Sea Region--History--18th century--Congresses.