Columbia subject headings:
Catholic Church--Foreign relations--Poland.
Pius XII, Pope, 1876-1958--Correspondence.
Pius XII, Pope, 1876-1958.
Poland--Foreign relations--Catholic Church.
Harvard subject headings:
Catholic Church--Foreign relations--Poland.
Pius XII, Pope, 1876-1958--Correspondence.
Pius XII, Pope, 1876-1958.
Poland--Foreign relations--Catholic Church
Princeton subject headings: