Columbia subject headings:
Harvard subject headings:
Castile (Spain)--Economic conditions--Congresses.
Castile (Spain)--Social conditions--Congresses.
Families--Leon (Kingdom)--Congresses.
Families--Spain--Castile--Congresses.
Leon (Kingdom)--Economic conditions--Congresses.
Leon (Kingdom)--Social conditions--Congresses.
Power (Social sciences)--Congresses
Princeton subject headings:
Families--Spain--Castilla y León--History--Congresses.