Columbia subject headings:
Harvard subject headings:
Cities and towns--Social aspects--Mexico.
Cities and towns--Social aspects--Spain.
Sociology, Urban--Mexico.
Sociology, Urban--Spain.
Princeton subject headings:
Cities and towns--Social aspects--Mexico--Congresses.
Cities and towns--Social aspects--Spain--Congresses.
Sociology, Urban--Mexico--Congresses.
Sociology, Urban--Spain--Congresses.