Columbia subject headings:
Harvard subject headings:
Catholic Church--Foreign relations--Poland--History--20th century.
Catholic Church--Poland--History--20th century.
Poland--Church history--20th century
Poland--Foreign relations--Catholic Church--History--20th century.
World War, 1939-1945--Religious aspects--Catholic Church
Princeton subject headings:
Catholic Church--Foreign relations.
Pius XII, Pope, 1876-1958.
Poland--Church history--20th century.
Poland--History--Occupation, 1939-1945.
Poland--History--Religious aspects--Catholic Church.
World War, 1939-1945--Catholic Church.