Columbia subject headings:
Harvard subject headings:
Catholic Church--Foreign relations--Spain--Congresses.
Papacy--History--20th century--Congresses.
Paul VI, Pope, 1897-1978--Congresses.
Spain--Foreign relations--Catholic Church--Congresses.
Princeton subject headings:
Catholic Church--Foreign relations--Spain--Congresses.
Catholic Church--Spain--History--20th century--Congresses.
Paul VI, Pope, 1897-1978--Congresses.
Spain--Church history--20th century--Congresses.
Spain--Foreign relations--Catholic Church--Congresses.