Subject
United States Foreign relations
7
Soviet Union Foreign relations
5
China Foreign relations
4
History
4
World War, 1939-1945
4
World politics
4
Dredging spoil Environmental aspects
3
Japan History
3
Middle East Foreign relations
3
United States Relations
3
Asia Politics and government
2
Asia Relations
2
China
2
Europe Foreign relations
2
Jewish-Arab relations
2
Middle East Politics and government
2
Public opinion
2
Vietnam War, 1961-1975
2
World War, 1939-1945 Campaigns
2
World War, 1939-1945 Diplomatic history
2
World War, 1939-1945 Territorial questions
2
Aeronautics Technological innovations History
1
Afghanistan History
1
Africa Foreign relations
1
Africa History
1
Africa Politics and government
1
Africa Relations
1
Africa, Central History
1
Africa, East Relations
1
Aquacultural engineering
1
Asia Defenses
1
Asia Economic conditions
1
Asia Foreign relations
1
Asia, Eastern Foreign relations
1
Basques History
1
Bioaccumulation
1
Cabinet officers
1
Canada English-French relations
1
China Civilization
1
China Foreign economic relations
1
China Intellectual life
1
China Politics and government
1
China Relations
1
Cities and towns History
1
Cities and towns in art
1
Cities and towns in literature
1
City and town life History
1
City and town life in art
1
City and town life in literature
1
Climatic changes
1
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