Columbia subject headings:
Baltic Sea Region.
Environmental protection--Baltic Sea Region--International cooperation.
Environmental protection--Baltic Sea Region.
National security--Environmental aspects--Baltic Sea Region.
Natural resources--Baltic Sea Region--International cooperation.
Security, International.
Harvard subject headings:
Environmental protection--Baltic Sea Region.
Princeton subject headings:
Baltic Sea Region.
Environmental protection--Baltic Sea Region--International cooperation.
Natural resources--Baltic Sea Region--International cooperation.
Security, International.