Columbia subject headings:
Cities and towns--Portugal--Congresses.
Cities and towns--Portugal--Growth--Congresses.
Cities and towns--Portugal--History--Congresses.
Cities and towns--Spain--Congresses.
Cities and towns--Spain--Growth--Congresses.
Cities and towns--Spain--History--Congresses.
Harvard subject headings:
Cities and towns--Portugal--Congresses.
Cities and towns--Portugal--Growth--Congresses.
Cities and towns--Portugal--History--Congresses.
Cities and towns--Spain--Congresses.
Cities and towns--Spain--Growth--Congresses.
Cities and towns--Spain--History--Congresses.
Princeton subject headings:
Cities and towns--Portugal--Congresses.
Cities and towns--Portugal--Growth--Congresses.
Cities and towns--Portugal--History--Congresses.
Cities and towns--Spain--Congresses.
Cities and towns--Spain--Growth--Congresses.
Cities and towns--Spain--History--Congresses.