Columbia subject headings:
Harvard subject headings:
Associations, institutions, etc.--Mexico--History--Congresses.
Associations, institutions, etc.--Spain--History--Congresses.
Basques--Mexico--History--Congresses.
Mexico--Economic conditions--Congresses.
Real Sociedad Vascongada de Amigos del País--Congresses.
Science--Mexico--History--Congresses.
Princeton subject headings:
Associations, institutions, etc.--Mexico--History--Congresses.
Associations, institutions, etc.--Spain--History--Congresses.
Basques--Mexico--History--Congresses.
Mexico--Economic conditions--Congresses.
Real Sociedad Vascongada de Amigos del País--Congresses.
Science--Mexico--History--Congresses.