Columbia subject headings:
Harvard subject headings:
Czechoslovakia--History--Intervention, 1968.
Czechoslovakia--Military relations--Germany (East)
Czechoslovakia. Armáda--History.
Germany (East)--History--20th century.
Germany (East)--Military relations--Czechoslovakia.
Germany (East). Nationale Volksarmee--History.
Warsaw Treaty Organization--Armed Forces--Czechoslovakia.
Warsaw Treaty Organization--Armed Forces--Germany (East)
Warsaw Treaty Organization--Armed Forces--History.
Princeton subject headings:
Czechoslovakia--History--Intervention, 1968.
Czechoslovakia--Military relations--Germany (East).
Czechoslovakia. Armáda--History.
Germany (East)--History--20th century.
Germany (East)--Military relations--Czechoslovakia.
Germany (East). Nationale Volksarmee--History.
Warsaw Treaty Organization--Armed Forces--Czechoslovakia.
Warsaw Treaty Organization--Armed Forces--Germany (East).
Warsaw Treaty Organization--Armed Forces--History.