Columbia subject headings:
Espionage--Ireland.
Ireland--Foreign relations--Great Britain.
Ireland--Foreign relations--United States.
Ireland--History--20th century.
Neutrality--Ireland.
World War, 1939-1945--Diplomatic history.
Harvard subject headings:
Espionage--Ireland.
Ireland--Foreign relations--Great Britain.
Ireland--Foreign relations--United States.
Ireland--History--20th century.
Neutrality--Ireland.
World War, 1939-1945--Diplomatic history.
Princeton subject headings:
Espionage--Ireland.
Ireland--Foreign relations--Great Britain.
Ireland--Foreign relations--United States.
Ireland--History--20th century.
Neutrality--Ireland.
World War, 1939-1945--Diplomatic history.