Columbia subject headings:
Harvard subject headings:
Architecture--Mexico--Mexico City--Congresses.
Centro Histórico de la Ciudad de México (Mexico City, Mexico)--History--Congresses.
Historic buildings--Mexico--Mexico City--Congresses.
Historic buildings--Mexico--Mexico City--History--Congresses.
Mexico City (Mexico)--Buildings, structures, etc.--History--Congresses.
Mexico City (Mexico)--History--Congresses.
Princeton subject headings:
Architecture--Mexico--Mexico City--Congresses.
Centro Histórico de la Ciudad de México (Mexico City, Mexico)--History--Congresses.
Historic buildings--Mexico--Mexico City--Congresses.
Mexico City (Mexico)--History--Congresses.